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Sample records for c91 test projectile

  1. EMGWS, D1 projectile tests

    International Nuclear Information System (INIS)

    This paper reports on the 90 mm EMGWS D1 Projectile which is an unguided projectile that is designed for launch from an Electromagnetic gun to achieve significant armor penetration. It is being developed under the broader program called Electromagnetic Gun Weapon System (EMGWS) which is sponsored by DARPA, DNA, and the U.S. Army. The 90 mm D1 Type II 'workhorse' Projectile is used to prove out material strength, fabrication techniques, and projectile structural integrity. The type II flight projectile is designed to allow maximum stress levels of 100-ksi when launched at 100-kilogees peak acceleration. The total weight of the projectile is 2.0 kg to attain a muzzle velocity of 3.0 km/s from a 9-Megajoule EM Gun. The Type II projectile configuration employs a tungsten nosetip plus 12 segmented tungsten penetrators, a two-piece aluminum discarding sabot, an aluminum pusher plate, and a nylon obturator. The pusher plate can incorporate either a solid or plasma armature

  2. Design and testing of high-pressure railguns and projectiles

    Science.gov (United States)

    Peterson, D. R.; Fowler, C. M.; Cummings, C. E.; Kerrisk, J. F.; Parker, J. V.; Marsh, S. P.; Adams, D. F.

    1984-03-01

    Attention is given to the results of high-pressure tests involving four railgun designs and four projectile types. Explosive magnetic-flux compression generators were employed to power the railguns. On the basis of the experimental data, it appears that the high-strength projectiles have lower resistance to acceleration than low-strength projectiles, which expand against the bore during acceleration. While confined in the bore, polycarbonate projectiles can be subjected to pressures as high as 1.3 GPa without shattering. In multishot railguns, it is important to prevent an accumulation of sooty material from the plasma armature in railgun seams.

  3. Lightweight Exoatmospheric Projectile (LEAP) test program. Supplemental environmental assessment

    Science.gov (United States)

    1992-06-01

    The proposed action is to modify previously planned Lightweight Exoatmospheric Projectile (LEAP) Test Program activities (LEAP EA, July 1991, Ref 32) at White Sands Missile Range (WSMR), New Mexico; Kwajalein Missile Range (KMR), U.S. Army Kwajalein Atoll (USAKA); and Wake Island. The proposed action includes modifications of flight trajectories for LEAP flights 3, 5, and 6. Two additional flights, LEAP-X and LEAP-7 have been added to the program. LEAP-X is a single rocket test flight from KMR and LEAP-7 is a two-rocket test flight from KMR and Wake Island. Component/assembly ground tests will take place at Orbital Sciences Corporation (OSC), Space Data Division (SDD), Chandler, Arizona; Phillips Laboratory, Edwards Air Force Base, California; Rocketdyne Division of Rockwell International; Boeing Aerospace and Electronics, Kent, Washington; Hughes Aircraft Corporation, Missile Systems Group, Canoga Park California; Aerojet, Sacramento, California; and Thiokol Corporation, Elkton, Maryland.

  4. Design of an Impact Test for Estimating the Deformation Energies of Projectiles in Wound Ballistics Studies

    OpenAIRE

    M. Jauhari; Bandyopadhyay, A

    1980-01-01

    The paper suggests an impact test which can be used to evaluate the deformation energies of small arm projectiles. Such an evaluation is of significance in wound ballistics studies while determining the amount of energy actually consumed in causing cavitation. Various sources of error inherent in the test have been discussed and it has been concluded that although approximate, the test can serve the useful purpose of providing a basis for interpreting the energy loss figures in gel on a ratio...

  5. Determine ISS Soyuz Orbital Module Ballistic Limits for Steel Projectiles Hypervelocity Impact Testing

    Science.gov (United States)

    Lyons, Frankel

    2013-01-01

    A new orbital debris environment model (ORDEM 3.0) defines the density distribution of the debris environment in terms of the fraction of debris that are low-density (plastic), medium-density (aluminum) or high-density (steel) particles. This hypervelocity impact (HVI) program focused on assessing ballistic limits (BLs) for steel projectiles impacting the enhanced Soyuz Orbital Module (OM) micrometeoroid and orbital debris (MMOD) shield configuration. The ballistic limit was defined as the projectile size on the threshold of failure of the OM pressure shell as a function of impact speeds and angle. The enhanced OM shield configuration was first introduced with Soyuz 30S (launched in May 2012) to improve the MMOD protection of Soyuz vehicles docked to the International Space Station (ISS). This test program provides HVI data on U.S. materials similar in composition and density to the Russian materials for the enhanced Soyuz OM shield configuration of the vehicle. Data from this test program was used to update ballistic limit equations used in Soyuz OM penetration risk assessments. The objective of this hypervelocity impact test program was to determine the ballistic limit particle size for 440C stainless steel spherical projectiles on the Soyuz OM shielding at several impact conditions (velocity and angle combinations). This test report was prepared by NASA-JSC/ HVIT, upon completion of tests.

  6. Design of an Impact Test for Estimating the Deformation Energies of Projectiles in Wound Ballistics Studies

    Directory of Open Access Journals (Sweden)

    M. Jauhari

    1980-04-01

    Full Text Available The paper suggests an impact test which can be used to evaluate the deformation energies of small arm projectiles. Such an evaluation is of significance in wound ballistics studies while determining the amount of energy actually consumed in causing cavitation. Various sources of error inherent in the test have been discussed and it has been concluded that although approximate, the test can serve the useful purpose of providing a basis for interpreting the energy loss figures in gel on a rational and scientific basis.

  7. LX-04 VIOLENCE MEASUREMENTS- STEVEN TESTS IMPACTED BY PROJECTILES SHOT FROM A HOWITZER GUN

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; Vandersall, K S; Switzer, L L; Tarver, C M

    2005-07-18

    Characterization of the reaction violence of LX-04 explosive (85% HMX and 15% Viton A by weight) was obtained from Steven Impact Tests performed above the reaction initiation threshold. A 155 mm Howitzer propellant driven gas gun was used to accelerate the Steven Test projectiles in the range of approximately 170-300 m/s to react (ignite) the LX-04 explosive. Blast overpressure gauges, acoustic microphones, and high-speed photography characterized the level of high explosive reaction violence. A detonation in this velocity range was not observed and when comparing these results (and the Susan test results) with that of other HMX based explosives, LX-04 has a more gradual reaction violence slope as the impact velocity increases. The high binder content (15%) of the LX-04 explosive is believed to be the key factor to the lower level of violence.

  8. LX-04 VIOLENCE MEASUREMENTS- STEVEN TESTS IMPACTED BY PROJECTILES SHOT FROM A HOWITZER GUN

    International Nuclear Information System (INIS)

    Characterization of the reaction violence of LX-04 explosive (85% HMX and 15% Viton A by weight) was obtained from Steven Impact Tests performed above the reaction initiation threshold. A 155 mm Howitzer propellant driven gas gun was used to accelerate the Steven Test projectiles in the range of approximately 170-300 m/s to react (ignite) the LX-04 explosive. Blast overpressure gauges, acoustic microphones, and high-speed photography characterized the level of high explosive reaction violence. A detonation in this velocity range was not observed and when comparing these results (and the Susan test results) with that of other HMX based explosives, LX-04 has a more gradual reaction violence slope as the impact velocity increases. The high binder content (15%) of the LX-04 explosive is believed to be the key factor to the lower level of violence

  9. Experimental Tests of the Proportionality of Aerodynamic Drag to Air Density for Supersonic Projectiles

    OpenAIRE

    Courtney, Elya; Courtney, Amy; Courtney, Michael

    2015-01-01

    Pure theory recognizes the dependence of supersonic drag coefficients on both Mach number and Reynolds number, which includes an implicit dependence of drag coefficient on air density. However, many modern approaches to computing trajectories for artillery and small arms treat drag coefficients as a function of Mach number and assume no dependence on Reynolds number. If drag force is strictly proportional to air density for supersonic projectiles (as suggested by applied theory), the drag coe...

  10. Experimental Tests of the Proportionality of Aerodynamic Drag to Air Density for Supersonic Projectiles

    CERN Document Server

    Courtney, Elya; Courtney, Michael

    2015-01-01

    Pure theory recognizes the dependence of supersonic drag coefficients on both Mach number and Reynolds number, which includes an implicit dependence of drag coefficient on air density. However, many modern approaches to computing trajectories for artillery and small arms treat drag coefficients as a function of Mach number and assume no dependence on Reynolds number. If drag force is strictly proportional to air density for supersonic projectiles (as suggested by applied theory), the drag coefficient should be independent of air density over a range of Mach numbers. Experimental data to directly support this are not widely available for supersonic projectiles. The experiment determined drag on a 2.59 g projectile from M1.2 to M2.9 using optical chronographs to measure initial and final velocities over a separation of 91.44 m. The free flight determination of drag coefficients was performed at two significantly different atmospheric densities (0.93 kg/m3 and 1.15 kg/m3 ). This experiment supported direct propo...

  11. Results of field testing with the FightSight infrared-based projectile tracking and weapon-fire characterization technology

    Science.gov (United States)

    Snarski, Steve; Menozzi, Alberico; Sherrill, Todd; Volpe, Chris; Wille, Mark

    2010-04-01

    This paper describes experimental results from recent live-fire data collects that demonstrate the capability of a prototype system for projectile detection and tracking. This system, which is being developed at Applied Research Associates, Inc., under the FightSight program, consists of a high-speed thermal camera and sophisticated image processing algorithms to detect and track projectiles. The FightSight operational vision is automated situational intelligence to detect, track, and graphically map large-scale firefights and individual shooting events onto command and control (C2) systems in real time (shot location and direction, weapon ID, movements and trends). Gaining information on enemy-fire trajectories allows educated inferences on the enemy's intent, disposition, and strength. Our prototype projectile detection and tracking system has been tested at the Joint Readiness Training Center (Ft Polk, LA) during live-fire convoy and mortar registration exercises, in the summer of 2009. It was also tested during staged military-operations- on-urban-terrain (MOUT) firefight events at Aberdeen Test Center (Aberdeen, MD) under the Hostile Fire Defeat Army Technology Objective midterm experiment, also in the summer of 2009, where we introduced fusion with acoustic and EO sensors to provide 3D localization and near-real time display of firing events. Results are presented in this paper that demonstrate effective and accurate detection and localization of weapon fire (5.56mm, 7.62mm, .50cal, 81/120mm mortars, 40mm) in diverse and challenging environments (dust, heat, day and night, rain, arid open terrain, urban clutter). FightSight's operational capabilities demonstrated under these live-fire data collects can support closecombat scenarios. As development continues, FightSight will be able to feed C2 systems with a symbolic map of enemy actions.

  12. Soft projectile impacts on thin reinforced concrete slabs: tests, modelling and simulations

    International Nuclear Information System (INIS)

    Numerical simulations of reinforced concrete structures subjected to high velocity impacts and explosions remain a difficult task today. Since ten years and more now, the CEA-Gramat has maintained a continuous research effort with the help of different French universities in order to overcome encountered difficulties in modelling the behaviour of concrete structures under severe loading. These difficulties are related to numerical aspects (convergence difficulties of the non linear stress strain relation in 3D configuration, efficiency of the numerical procedure and robustness), but also due to the ability of the material model to simulate the accurately behaviour of a very complex and heterogeneous material like concrete. A new concrete model, named PRM model, has been developed at CEA-Gramat (Pontiroli, Rouquand and Mazars) to predict the concrete response under a large range of dynamic loadings. Works presented in this paper have been performed in the framework of the French VULCAIN PGCU 2007 research project (founded by the French National Research Agency). This project aims at defining a theoretical and probabilistic methodology in order to assess the structural safety of industrial structures that might be submitted to transient loadings such as blasts or impacts generated by various projectiles. A complementary objective is to improve diagnosis, prevention or protection actions. This scientific program gathers well-known and complementary scientific institutes, firms and universities in France. (authors)

  13. Electromagnetic diagnostic techniques for hypervelocity projectile detection, velocity measurement, and size characterization: Theoretical concept and first experimental test

    International Nuclear Information System (INIS)

    A new measurement technique is suggested to augment the characterization and understanding of hypervelocity projectiles before impact. The electromagnetic technique utilizes magnetic diffusion principles to detect particles, measure velocity, and indicate relative particle dimensions. It is particularly suited for detection of small particles that may be difficult to track utilizing current characterization methods, such as high-speed video or flash radiography but can be readily used for large particle detection, where particle spacing or location is not practical for other measurement systems. In this work, particles down to 2 mm in diameter have been characterized while focusing on confining the detection signal to enable multi-particle characterization with limited particle-to-particle spacing. The focus of the paper is on the theoretical concept and the analysis of its applicability based on analytical and numerical calculation. First proof-of-principle experimental tests serve to further validate the method. Some potential applications are the characterization of particles from a shaped-charge jet after its break-up and investigating debris in impact experiments to test theoretical models for the distribution of particles size, number, and velocity

  14. Electromagnetic diagnostic techniques for hypervelocity projectile detection, velocity measurement, and size characterization: Theoretical concept and first experimental test

    Science.gov (United States)

    Uhlig, W. Casey; Heine, Andreas

    2015-11-01

    A new measurement technique is suggested to augment the characterization and understanding of hypervelocity projectiles before impact. The electromagnetic technique utilizes magnetic diffusion principles to detect particles, measure velocity, and indicate relative particle dimensions. It is particularly suited for detection of small particles that may be difficult to track utilizing current characterization methods, such as high-speed video or flash radiography but can be readily used for large particle detection, where particle spacing or location is not practical for other measurement systems. In this work, particles down to 2 mm in diameter have been characterized while focusing on confining the detection signal to enable multi-particle characterization with limited particle-to-particle spacing. The focus of the paper is on the theoretical concept and the analysis of its applicability based on analytical and numerical calculation. First proof-of-principle experimental tests serve to further validate the method. Some potential applications are the characterization of particles from a shaped-charge jet after its break-up and investigating debris in impact experiments to test theoretical models for the distribution of particles size, number, and velocity.

  15. Investigation on the Artificial Bird Projectile used in Bird Strike Test%用于鸟撞试验的仿真鸟弹研究

    Institute of Scientific and Technical Information of China (English)

    刘小川; 郭军; 孙侠生; 陈建新; 张建军; 苗娟

    2012-01-01

    An artificial bird projectile used in aircraft structure against bird strike experiment was developed. Its basic compositions are gelatine and water. Density is a key parameter controlled by special manufacturing process and adding quenched and tempered materials. The dimension and weight of artificial bird projectile are guaranteed by the mold. Thus, a 1. 8kg standard form of bird projectile was manufactured to meet the regulatory requirements. Three real bird strike tests and one artificial bird strike comparative test were carried out. The target is four aluminium plates with 12mm thickness. Results show that the artificial bird projectile has sufficient strength and can withstand launch overload. The dynamic deformation mode and the dynamic strain response time history of structure of artificial bird projectile are basicly consistent with real bird. The maximum difference of structure dynamic strain response is only 3. 2%; while the difference of structure residual deformation is 8. 7%. Above results prove that the artificial bird projectile developed in this paper can substitute real bird in bird strike experiment.%对用于飞机结构抗鸟撞试验的仿真鸟弹进行了研究,给出了配方,其基体材料为明胶和水.密度是仿真鸟弹的关键参数,通过工艺流程和添加调质材料对其进行控制.鸟弹外形尺寸和重量由模具保证,制作出了满足规范要求的1.8kg标准形态鸟弹.利用4块12mm厚的铝板,进行了3次真实鸟弹试验和1次仿真鸟弹的鸟撞对比试验.试验结果表明,仿真鸟弹具有足够的强度可承受发射过载.同时仿真鸟弹与真实鸟弹的动态变形模式以及结构动态应变响应时间历程基本一致.其结构动态应变响应最大值仅相差3.2%,而结构残余变形相差8.7%.上述结果证明了本文研制的仿真鸟弹可以在结构抗鸟撞试验研究中替代真实鸟弹.

  16. The EMET railgun projectile

    Energy Technology Data Exchange (ETDEWEB)

    Burton, R.L.; Witherspoon, F.D.; Goldstein, S.A. (Gruy Federal, Inc., Arlington, VA (United States))

    1991-01-01

    This paper reports on the EMET projectile which uses joule heating to accelerate the projectile in a railgun with a predominantly electrothermal driving force. The structure is designed to conduct armature current within a thin annular band around the shank of the large L/D dumbbell-shaped projectile. Current is initiated by a fuse located around the shank, and an impedance of 8 m{Omega} is achieved, compared to the 1-2 m{Omega} observed for EM guns. A supersonic nozzle in the projectile tail section expands and cools the armature plasma to raise its resistivity, prevent secondary arcs and provide additional accelerating thrust. Experimental data is presented for 9.5 mm diameter, 5 gm projectiles, accelerated to nearly 600 m/sec at 55 kA in a 0.9 m railgun. The armature remains confined in the projectile structure, and 75% of the acceleration is provided electrothermally.

  17. Fired missile projectiles

    International Nuclear Information System (INIS)

    This paper reports ferromagnetic properties of fired missile projectiles (bullets, BBs, etc) investigated. Projectile samples were obtained from manufactures, police, and commercial sources. Deflection measurements at the portal of a 1.5-T magnetic field were performed for 47 projectiles. Sixteen bullets were examined in gelatin phantoms for rotation-translation movements as well. Ferromagnetic bullets displayed considerable deflection forces in the presence of the magnetic field and could be rotated to 80 degrees from their previous alignments when introduced perpendicular to the magnetic field in our gelatin phantom experiments. Military bullet calibers appear to pose the greatest ferromagnetic risk. Commercial sporting ammunition is generally nonferromagnetic

  18. Small caliber guided projectile

    Science.gov (United States)

    Jones, James F.; Kast, Brian A.; Kniskern, Marc W.; Rose, Scott E.; Rohrer, Brandon R.; Woods, James W.; Greene, Ronald W.

    2010-08-24

    A non-spinning projectile that is self-guided to a laser designated target and is configured to be fired from a small caliber smooth bore gun barrel has an optical sensor mounted in the nose of the projectile, a counterbalancing mass portion near the fore end of the projectile and a hollow tapered body mounted aft of the counterbalancing mass. Stabilizing strakes are mounted to and extend outward from the tapered body with control fins located at the aft end of the strakes. Guidance and control electronics and electromagnetic actuators for operating the control fins are located within the tapered body section. Output from the optical sensor is processed by the guidance and control electronics to produce command signals for the electromagnetic actuators. A guidance control algorithm incorporating non-proportional, "bang-bang" control is used to steer the projectile to the target.

  19. Projectile Demilitarization Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Projectile Wash Out Facility is US Army Ammunition Peculiar Equipment (APE 1300). It is a pilot scale wash out facility that uses high pressure water and steam...

  20. The Effect of Soil Parameters on Earth Penetration of Projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, L J; Ferguson, III, G H; Murff, J D; Cetiner, A

    1969-07-01

    The purpose of this study can be divided into the three following parts: 1) to present complete sets of data obtained for projectile penetration into soil targets of precisely known properties, and to describe how to build and test these targets; 2) to present a numerical method of data analysis for empirically determining the force on a projectile, during penetration; and 3) to demonstrate how physical soil parameters, as well as impact velocity and a projectile property influence penetration.

  1. Hydrodynamic Drag on Streamlined Projectiles and Cavities

    KAUST Repository

    Jetly, Aditya

    2016-04-19

    The air cavity formation resulting from the water-entry of solid objects has been the subject of extensive research due to its application in various fields such as biology, marine vehicles, sports and oil and gas industries. Recently we demonstrated that at certain conditions following the closing of the air cavity formed by the initial impact of a superhydrophobic sphere on a free water surface a stable streamlined shape air cavity can remain attached to the sphere. The formation of superhydrophobic sphere and attached air cavity reaches a steady state during the free fall. In this thesis we further explore this novel phenomenon to quantify the drag on streamlined shape cavities. The drag on the sphere-cavity formation is then compared with the drag on solid projectile which were designed to have self-similar shape to that of the cavity. The solid projectiles of adjustable weight were produced using 3D printing technique. In a set of experiments on the free fall of projectile we determined the variation of projectiles drag coefficient as a function of the projectiles length to diameter ratio and the projectiles specific weight, covering a range of intermediate Reynolds number, Re ~ 104 – 105 which are characteristic for our streamlined cavity experiments. Parallel free fall experiment with sphere attached streamlined air cavity and projectile of the same shape and effective weight clearly demonstrated the drag reduction effect due to the stress-free boundary condition at cavity liquid interface. The streamlined cavity experiments can be used as the upper bound estimate of the drag reduction by air layers naturally sustained on superhydrophobic surfaces in contact with water. In the final part of the thesis we design an experiment to test the drag reduction capacity of robust superhydrophobic coatings deposited on the surface of various model vessels.

  2. Subcaliber discarding sabot airgun projectiles.

    Science.gov (United States)

    Frank, Matthias; Schönekeß, Holger; Herbst, Jörg; Staats, Hans-Georg; Ekkernkamp, Axel; Nguyen, Thanh Tien; Bockholdt, Britta

    2014-03-01

    Medical literature abounds with reports on injuries and fatalities caused by airgun projectiles. While round balls or diabolo pellets have been the standard projectiles for airguns for decades, today, there are a large number of different airgun projectiles available. A very uncommon--and until now unique--discarding sabot airgun projectile (Sussex Sabo Bullet) was introduced into the market in the 1980s. The projectile, available in 0.177 (4.5 mm) and 0.22 (5.5 mm) caliber, consists of a plastic sabot cup surrounding a subcaliber copper-coated lead projectile in typical bullet shape. Following the typical principle of a discarding sabot projectile, the lightweight sabot is supposed to quickly loose velocity and to fall to the ground downrange while the bullet continues on target. These sabot-loaded projectiles are of special forensic interest due to their non-traceability and ballistic parameters. Therefore, it is the aim of this work to investigate the ballistic performance of these sabot airgun projectiles by high-speed video analyses and by measurement of the kinetic parameters of the projectile parts by a transient recording system as well as observing their physical features after being fired. While the sabot principle worked properly in high-energy airguns (E > 17 J), separation of the core projectile from the sabot cup was also observed when discharged in low-energy airguns (E < 7.5 J). While the velocity of the discarded Sussex Sabo core projectile was very close to the velocity of a diabolo-type reference projectile (RWS Meisterkugel), energy density was up to 60 % higher. To conclude, this work is the first study to demonstrate the regular function of this uncommon type of airgun projectile. PMID:24263305

  3. Physics of projectile fragments

    International Nuclear Information System (INIS)

    This is a study report on the polarization phenomena of the projectile fragments produced by heavy ion reactions, and the beta decay of fragments. The experimental project by using heavy ions with the energy from 50 MeV/amu to 250 MeV/amu was designed. Construction of an angle-dispersion spectrograph for projectile fragments was proposed. This is a two-stage spectrograph. The first stage is a QQDQQ type separator, and the second stage is QDQD type. Estimation shows that Co-66 may be separated from the nuclei with mass of 65 and 67. The orientation of fragments can be measured by detecting beta-ray. The apparatus consists of a uniform field magnet, an energy absorber, a stopper, a RF coil and a beta-ray hodoscope. This system can be used for not only this purpose but also for the measurement of hyperfine structure. (Kato, T.)

  4. Penetration of rod projectiles in semi-infinite targets : a validation test for Eulerian X-FEM in ALEGRA.

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byoung Yoon; Leavy, Richard Brian [U.S. Army Research Laboratory, Aberdeen Proving Grounds, MD; Niederhaus, John Henry J.

    2013-03-01

    The finite-element shock hydrodynamics code ALEGRA has recently been upgraded to include an X-FEM implementation in 2D for simulating impact, sliding, and release between materials in the Eulerian frame. For validation testing purposes, the problem of long-rod penetration in semi-infinite targets is considered in this report, at velocities of 500 to 3000 m/s. We describe testing simulations done using ALEGRA with and without the X-FEM capability, in order to verify its adequacy by showing X-FEM recovers the good results found with the standard ALEGRA formulation. The X-FEM results for depth of penetration differ from previously measured experimental data by less than 2%, and from the standard formulation results by less than 1%. They converge monotonically under mesh refinement at first order. Sensitivities to domain size and rear boundary condition are investigated and shown to be small. Aside from some simulation stability issues, X-FEM is found to produce good results for this classical impact and penetration problem.

  5. Measurement of Spin of Projectiles

    Directory of Open Access Journals (Sweden)

    S. R. Verma

    1989-01-01

    Full Text Available Hitherto the spin of the projectile has been measured with the help of spin loop method (for magnetised projectiles and Multishot Ballistic Synchro method (for magnetised and non-magnetised projectiles. This paper discusses the method of measurement of spinwith a single ballistic synchro picture; the advantage of this method is that it dispenses with elaborate and precise optical alignment, required for Multishot Ballistic Synchro method.

  6. Experimental and numerical study on fragmentation of steel projectiles

    Directory of Open Access Journals (Sweden)

    Hopperstad O.S.

    2012-08-01

    Full Text Available A previous experimental study on penetration and perforation of circular Weldox 460E target plates with varying thicknesses struck by blunt-nose projectiles revealed that fragmentation of the projectile occurred if the target thickness or impact velocity exceeded a certain value. Thus, numerical simulations that do not account for fragmentation during impact can underestimate the perforation resistance of protective structures. Previous numerical studies have focused primarily on the target plate behaviour. This study considers the behaviour of the projectile and its possible fragmentation during impact. Hardened steel projectiles were launched at varying velocities in a series of Taylor tests. The impact events were captured using a high-speed camera. Fractography of the fragmented projectiles showed that there are several fracture mechanisms present during the fragmentation process. Tensile tests of the projectile material revealed that the hardened material has considerable variations in yield stress and fracture stress and strain. In the finite element model, the stress-strain behaviour from tensile tests was used to model the projectile material with solid elements and the modified Johnson-Cook constitutive relation. Numerical simulations incorporating the variations in material properties are capable of reproducing the experimental fracture patterns, albeit the predicted fragmentation velocities are too low.

  7. Experimental and numerical study on fragmentation of steel projectiles

    Science.gov (United States)

    Råkvaag, K. G.; Børvik, T.; Hopperstad, O. S.; Westermann, I.

    2012-08-01

    A previous experimental study on penetration and perforation of circular Weldox 460E target plates with varying thicknesses struck by blunt-nose projectiles revealed that fragmentation of the projectile occurred if the target thickness or impact velocity exceeded a certain value. Thus, numerical simulations that do not account for fragmentation during impact can underestimate the perforation resistance of protective structures. Previous numerical studies have focused primarily on the target plate behaviour. This study considers the behaviour of the projectile and its possible fragmentation during impact. Hardened steel projectiles were launched at varying velocities in a series of Taylor tests. The impact events were captured using a high-speed camera. Fractography of the fragmented projectiles showed that there are several fracture mechanisms present during the fragmentation process. Tensile tests of the projectile material revealed that the hardened material has considerable variations in yield stress and fracture stress and strain. In the finite element model, the stress-strain behaviour from tensile tests was used to model the projectile material with solid elements and the modified Johnson-Cook constitutive relation. Numerical simulations incorporating the variations in material properties are capable of reproducing the experimental fracture patterns, albeit the predicted fragmentation velocities are too low.

  8. Comparison of less lethal 40 mm sponge projectile and the 37 mm projectile for injury assessment on human thorax

    Directory of Open Access Journals (Sweden)

    Oukara A.

    2012-08-01

    Full Text Available Since there is an increasing interest in avoiding human body injury in diverse situations like crowd control or peacekeeping missions, less lethal ammunition are more and more used. In this study we focus only on kinetic energy non-lethal (KENLW projectiles. Their desired effects on human body are the temporary incapacitation through blunt trauma. There are different types of KENLW projectiles ranging from rigid to deformable projectiles. Unfortunately, the effects of such projectiles are not really well known as it is difficult to measure the force transmitted to the human body or the related deformation. Because the potential of injury excludes human living tests, tests are performed on cadavers, animals or human tissue surrogates. Besides these tests, numerical simulations are more and more used to gain more understanding, to assess or to predict the effects of this kind of projectile on human body. In this paper a comparison based on the viscous criterion between the 37 mm rigid projectile and the 40 mm sponge projectile was made.

  9. 一维增程修正弹地面密集度的试验方法%Test Method for Dispersion of Extended Range for One-dimensional Trajectory Correction Projectile

    Institute of Scientific and Technical Information of China (English)

    舒延春

    2014-01-01

    一维增程修正弹的地面密集度是评价修正效果的重要战技指标,其试验方法与常规弹药射击密集度试验明显不同。依据一维增程修正弹的修正原则,利用落点散布的正态分布特性与双侧100a百分位点,确定密集度试验边界最低可接受值以及最佳“调节裕量”,并通过仿真计算得到最佳“调节裕量”随密集度的变化规律,为靶场进行一维增程修正弹密集度试验提供一定的借鉴。%It’s an important tactical and technical index of the ground artillery dispersion of extended range for one-dimensional trajectory correction projectile to evaluate its correction effect,and the test meth-od is different comparatively to the conventional artillery’s.Utilizing the characteristic of the ground atille-ry dispersion of normal distribution and double-sided 100a reference interval,the minimum acceptable bound value for the ground artillery dispersion test and the optimization regulated margin are ascertained by the correction principle of the one-dimensional trajectory correction projectile.At the same time,the best regulated margin of the changing law can be gained by the simulation on the different firing ground disper-sion.The results can provide references for One-dimensional Trajectory Correction Projectile on the firing consistency on the range test.

  10. Injury Risk Assessment of Non-Lethal Projectile Head Impacts

    OpenAIRE

    Oukara, Amar; Nsiampa, Nestor; Robbe, Cyril; Papy, Alexandre

    2014-01-01

    Kinetic energy non-lethal projectiles are used to impart sufficient effect onto a person in order to deter uncivil or hazardous behavior with a low probability of permanent injury. Since their first use, real cases indicate that the injuries inflicted by such projectiles may be irreversible and sometimes lead to death, especially for the head impacts. Given the high velocities and the low masses involved in such impacts, the assessment approaches proposed in automotive crash tests and sports ...

  11. High-speed imaging of supercavitating underwater projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Hrubes, J.D. [Naval Undersea Warfare Center, Newport, RI (United States)

    2001-01-01

    High-speed images of supercavitating underwater projectiles traveling up to and exceeding the speed of sound in water were captured using a variety of methods. These images reveal information on projectile flight behavior, stability mechanisms, cavity shape, and in-barrel launch characteristics. This information was used to understand the physics of supercavitating bodies, verify computer models, aid failure analysis, and produce projectile launch package design modifications. In the supersonic tests, projectile shock waves were revealed. Imaging consisted of standard video, 16-mm high-speed, laser illuminated motion pictures, high-speed gated intensified video, and stroboscope illuminated 35-mm still photography. Both front-lit and shadowgraph configurations were used. (orig.)

  12. Fragmentation of hypervelocity aluminum projectiles on fabrics

    Science.gov (United States)

    Rudolph, Martin; Schäfer, Frank; Destefanis, Roberto; Faraud, Moreno; Lambert, Michel

    2012-07-01

    This paper presents work performed for a study investigating the ability of different flexible materials to induce fragmentation of a hypervelocity projectile. Samples were chosen to represent a wide range of industrially available types of flexible materials like ceramic, aramid and carbon fabrics as well as a thin metallic mesh. Impact conditions and areal density were kept constant for all targets. Betacloth and multi-layer insulation (B-MLI) are mounted onto the targets to account for thermal system engineering requirements. All tests were performed using the Space light-gas gun facility (SLGG) of the Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut, EMI. Projectiles were aluminum spheres with 5 mm diameter impacting at approximately 6.3 km/s. Fragmentation was evaluated using a witness plate behind the target. An aramid and a ceramic fabric lead the ranking of fabrics with the best projectile fragmentation and debris cloud dispersion performance. A comparison with an equal-density rigid aluminum plate is presented. The work presented can be applied to optimize the micrometeoroid and space debris (MM/SD) shielding structure of inflatable modules.

  13. Orientation estimation algorithm applied to high-spin projectiles

    International Nuclear Information System (INIS)

    High-spin projectiles are low cost military weapons. Accurate orientation information is critical to the performance of the high-spin projectiles control system. However, orientation estimators have not been well translated from flight vehicles since they are too expensive, lack launch robustness, do not fit within the allotted space, or are too application specific. This paper presents an orientation estimation algorithm specific for these projectiles. The orientation estimator uses an integrated filter to combine feedback from a three-axis magnetometer, two single-axis gyros and a GPS receiver. As a new feature of this algorithm, the magnetometer feedback estimates roll angular rate of projectile. The algorithm also incorporates online sensor error parameter estimation performed simultaneously with the projectile attitude estimation. The second part of the paper deals with the verification of the proposed orientation algorithm through numerical simulation and experimental tests. Simulations and experiments demonstrate that the orientation estimator can effectively estimate the attitude of high-spin projectiles. Moreover, online sensor calibration significantly enhances the estimation performance of the algorithm. (paper)

  14. Whole-genome analysis of the ammonia-oxidizing bacterium, Nitrosomonas eutropha C91: implications for niche adaptation

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Lisa Y [University of California, Riverside; Arp, D J [Oregon State University; Berube, PM [University of Washington, Seattle; Chain, Patrick S. G. [Lawrence Livermore National Laboratory (LLNL); Hauser, Loren John [ORNL; Jetten, MSM [Radboud University Nijmegen; Klotz, Martin G [University of Louisville, Louisville; Larimer, Frank W [ORNL; Norton, Jeanette M. [Utah State University (USU); Op den Camp, HJM [Radboud University Nijmegen; Shin, M [U.S. Department of Energy, Joint Genome Institute; Wei, Xueming [Oregon State University

    2007-12-01

    Analysis of the structure and inventory of the genome of Nitrosomonas eutropha C91 revealed distinctive features that may explain the adaptation of N. eutropha-like bacteria to N-saturated ecosystems. Multiple gene-shuffling events are apparent, including mobilized and replicated transposition, as well as plasmid or phage integration events into the 2.66 Mbp chromosome and two plasmids (65 and 56 kbp) of N. eutropha C91. A 117 kbp genomic island encodes multiple genes for heavy metal resistance, including clusters for copper and mercury transport, which are absent from the genomes of other ammonia-oxidizing bacteria (AOB). Whereas the sequences of the two ammonia monooxygenase and three hydroxylamine oxidoreductase gene clusters in N. eutropha C91 are highly similar to those of Nitrosomonas europaea ATCC 19718, a break of synteny in the regions flanking these clusters in each genome is evident. Nitrosomonas eutropha C91 encodes four gene clusters for distinct classes of haem-copper oxidases, two of which are not found in other aerobic AOB. This diversity of terminal oxidases may explain the adaptation of N. eutropha to environments with variable O2 concentrations and/or high concentrations of nitrogen oxides. As with N. europaea, the N. eutropha genome lacks genes for urease metabolism, likely disadvantaging nitrosomonads in low-nitrogen or acidic ecosystems. Taken together, this analysis revealed significant genomic variation between N. eutropha C91 and other AOB, even the closely related N. europaea, and several distinctive properties of the N. eutropha genome that are supportive of niche specialization.

  15. A model for projectile fragmentation

    International Nuclear Information System (INIS)

    A model for projectile fragmentation is developed whose origin can be traced back to the Bevalac era. The model positions itself between the phenomenological EPAX parametrization and transport models like 'Heavy Ion Phase Space Exploration' (HIPSE) model and antisymmetrised molecular dynamics (AMD) model. A very simple impact parameter dependence of input temperature is incorporated in the model which helps to analyze the more peripheral collisions. The model is applied to calculate the charge, isotopic distributions, average number of intermediate mass fragments and the average size of largest cluster at different Zbound of different projectile fragmentation reactions at different energies.

  16. A model for projectile fragmentation

    CERN Document Server

    Chaudhuri, G; Gupta, S Das

    2012-01-01

    A model for projectile fragmentation is developed whose origin can be traced back to the Bevalac era. The model positions itself between the phenomenological EPAX parametrization and microscopic transport models like "Heavy Ion Phase Space Exploration" (HIPSE) model and antisymmetrised molecular dynamics (AMD) model. A very simple impact parameter dependence of input temperature is incorporated in the model which helps to analyze the more peripheral collisions. The model is applied to calculate the charge, isotopic distributions, average number of intermediate mass fragments and the average size of largest cluster at different $Z_{bound}$ of different projectile fragmentation reactions at different energies.

  17. Projectile penetration into ballistic gelatin.

    Science.gov (United States)

    Swain, M V; Kieser, D C; Shah, S; Kieser, J A

    2014-01-01

    Ballistic gelatin is frequently used as a model for soft biological tissues that experience projectile impact. In this paper we investigate the response of a number of gelatin materials to the penetration of spherical steel projectiles (7 to 11mm diameter) with a range of lower impacting velocities (number of predictive relationships available in the literature, it is found that over the range of projectiles and compositions used, the results fit a simple relationship that takes into account the projectile diameter, the threshold velocity for penetration into the gelatin and a value of the shear modulus of the gelatin estimated from the threshold velocity for penetration. The normalised depth is found to fit the elastic Froude number when this is modified to allow for a threshold impact velocity. The normalised penetration data are found to best fit this modified elastic Froude number with a slope of 1/2 instead of 1/3 as suggested by Akers and Belmonte (2006). Possible explanations for this difference are discussed. PMID:24184862

  18. Projectile Motion Without Trigonometric Functions

    Science.gov (United States)

    Mohazzabi, Pirooz; Kohneh, Zahra A.

    2005-02-01

    In this paper we provide a treatment of projectile motion that is accessible to students who are unfamiliar with trigonometry but do have a minimal knowledge of elementary algebra and know the Pythagorean theorem. In this approach, we view the initial velocity of the projectile as being a combination of a vertical part (component) v0V and a horizontal component v0H (see Fig. 1). This is in contrast to the usual approach of taking the initial speed v0 and the launch angle as being given. We let the initial position be the origin and neglect air drag. Assuming that the constant acceleration kinematics equations are known, we may write vH = v0H, and the horizontal distance traveled is x = v0H t, where t is the elapsed time. We also have vV = v0V - gt, where g is the magnitude of the acceleration due to gravity. And the vertical displacement is y = v0V t - ½ gt2. These equations may be used to find the location and velocity of the projectile at any time t. We can also find the equation of the path of the projectile by combining Eq. [1(b)] and Eq. [2(b)] to get y = -(g/2v0H2)x2 + (v0V/v0H) x, which is the equation of a concave-down parabola.

  19. Multiple impacts of dusty projectiles

    Science.gov (United States)

    Kothe, Stefan; Güttler, Carsten; Blum, Jurgen

    In the context of early stages of planetesimal formation we performed laboratory and drop tower experiments to study multiple impacts of small dust-aggregate projectiles into solid sintered dust targets. Both collision partners consisted of 1.5 µm monodisperse spherical SiO2 monomers with volume filling factors of 0.15 (projectiles) and 0.35 (targets), respectively. The fragile projectiles were accelerated by a solenoid accelerator with a linear projectile magazine, which enabled us to perform 25 impacts within 4.5 s of microgravity time in the Bremen drop tower. We measured the mass-accretion efficiency for different impact velocities between 3 and 5 m s-1 , using an analytical balance and imaging methods. Furthermore, we observed random collisions among small dust aggregates with sizes around 1 mm and collision velocities of the order of 0.25 m s-1 and used them to improve the dust-aggregate collision model of Güttler et al. (2010). u

  20. Projectile-generating explosive access tool

    Science.gov (United States)

    Jakaboski, Juan-Carlos; Hughs, Chance G; Todd, Steven N

    2013-06-11

    A method for generating a projectile using an explosive device that can generate a projectile from the opposite side of a wall from the side where the explosive device is detonated. The projectile can be generated without breaching the wall of the structure or container. The device can optionally open an aperture in a solid wall of a structure or a container and form a high-kinetic-energy projectile from the portion of the wall removed to create the aperture.

  1. An experimental study on the deformation and fracture modes of steel projectiles during impact

    International Nuclear Information System (INIS)

    Highlights: • The fracture process is ductile for the unhardened projectiles. • A combined ductile–brittle fracture process is obtained for the HRC 40 projectiles. • The fragmentation of HRC 52 projectiles has cleavage as the main mechanism. • The fracture modes were confirmed in a metallurgical study. • The hardened materials have a stochastic variation of the mechanical properties. - Abstract: Previous investigations of the penetration and perforation of high-strength steel plates struck by hardened steel projectiles have shown that under certain test conditions the projectile may fracture or even fragment upon impact. Simulations without an accurate failure description for the projectile material will then predict perforation of the target instead of fragmentation of the projectile, and thus underestimate the ballistic limit velocity of the target plate. This paper presents an experimental investigation of the various deformation and fracture modes that may occur in steel projectiles during impact. This is studied by conducting Taylor bar impact tests using 20 mm diameter, 80 mm long, tool steel projectiles with three different hardness values (HRC 19, 40 and 52). A gas gun was used to fire the projectiles into a rigid wall at impact velocities ranging from 100 to 350 m/s, and the deformation and fracture processes were captured by a high-speed video camera. From the tests, several different deformation and fracture modes were registered for each hardness value. To investigate the influence of material on the deformation and fracture modes, several series of tensile tests on smooth axisymmetric specimens were carried out to characterise the mechanical properties of the three materials. To gain a deeper understanding of the various processes causing fracture and fragmentation during impact, a metallurgical investigation was conducted. The fracture surfaces of the failed projectiles of different hardness were investigated, and the microstructure was

  2. Injury risk assessment of non-lethal projectile head impacts.

    Science.gov (United States)

    Oukara, Amar; Nsiampa, Nestor; Robbe, Cyril; Papy, Alexandre

    2014-01-01

    Kinetic energy non-lethal projectiles are used to impart sufficient effect onto a person in order to deter uncivil or hazardous behavior with a low probability of permanent injury. Since their first use, real cases indicate that the injuries inflicted by such projectiles may be irreversible and sometimes lead to death, especially for the head impacts. Given the high velocities and the low masses involved in such impacts, the assessment approaches proposed in automotive crash tests and sports may not be appropriate. Therefore, there is a need of a specific approach to assess the lethality of these projectiles. In this framework, some recent research data referred in this article as "force wall approach" suggest the use of three lesional thresholds (unconsciousness, meningeal damages and bone damages) that depend on the intracranial pressure. Three corresponding critical impact forces are determined for a reference projectile. Based on the principle that equal rigid wall maximal impact forces will produce equal damage on the head, these limits can be determined for any other projectile. In order to validate the consistence of this innovative method, it is necessary to compare the results with other existing assessment methods. This paper proposes a comparison between the "force wall approach" and two different head models. The first one is a numerical model (Strasbourg University Finite Element Head Model-SUFEHM) from Strasbourg University; the second one is a mechanical surrogate (Ballistics Load Sensing Headform-BLSH) from Biokinetics. PMID:25400712

  3. Projectiles, pendula, and special relativity

    CERN Document Server

    Price, R H

    2005-01-01

    The kind of flat-earth gravity used in introductory physics appears in an accelerated reference system in special relativity. From this viewpoint, we work out the special relativistic description of a ballistic projectile and a simple pendulum, two examples of simple motion driven by earth-surface gravity. The analysis uses only the basic mathematical tools of special relativity typical of a first-year university course.

  4. Using Tracker as a Pedagogical Tool for Understanding Projectile Motion

    CERN Document Server

    Wee, Loo Kang; Goh, Giam Hwee; Tan, Samuel; Lee, Tat Leong

    2012-01-01

    This paper reports the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When computer model building learning processes is supported and driven by video analysis data, this free Open Source Physics (OSP) tool can provide opportunities for students to engage in active inquiry-based learning. We discuss the pedagogical use of Tracker to address some common misconceptions of projectile motion by allowing students to test their hypothesis by juxtaposing their mental models against the analysis of real life videos. Initial research findings suggest that allowing learners to relate abstract physics concepts to real life through coupling computer modeling with traditional video analysis could be an innovative and effective way to learn projectile motion.

  5. Using Tracker as a pedagogical tool for understanding projectile motion

    Science.gov (United States)

    Wee, Loo Kang; Chew, Charles; Hwee Goh, Giam; Tan, Samuel; Lee, Tat Leong

    2012-07-01

    This article reports on the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When a computer model building learning process is supported and driven by video analysis data, this free Open Source Physics tool can provide opportunities for students to engage in active enquiry-based learning. We discuss the pedagogical use of Tracker to address some common misconceptions concerning projectile motion by allowing students to test their hypothesis by juxtaposing their mental models against the analysis of real-life videos. Initial research findings suggest that allowing learners to relate abstract physics concepts to real life through coupling computer modelling with traditional video analysis could be an innovative and effective way to learn projectile motion.

  6. Semi-theoretical analyses of the concrete plate perforated by a rigid projectile

    Science.gov (United States)

    Wu, Hao; Fang, Qin; Zhang, Ya-Dong; Gong, Zi-Ming

    2012-12-01

    Based on the three-stage perforation model, a semi-theoretical analysis is conducted for the ballistic performances of a rigid kinetic projectile impacting on concrete plates. By introducing the projectile resistance coefficients, dimensionless formulae are proposed for depth of penetration (DOP), perforation limit thickness, ballistic limit velocity, residual velocity and perforation ratio, with the projectile nosed geometries and projectile-target interfacial friction taken into account. Based on the proposed formula for DOP and lots of penetration tests data of normal and high strength concrete targets, a new expression is obtained for target strength parameter. By comparisons between the results of the proposed formulae and existing empirical formulae and large amount of projectile penetration or perforation tests data for monolithic and segmented concrete targets, the validations of the proposed formulae are verified. It is found that the projectile-target interfacial friction can be neglected in the predictions of characteristic ballistic parameters. The dimensionless DOP for low-to-mid speed impacts of non-flat nosed projectiles increases almost linearly with the impact factor by a coefficient of 2/(π S). The anti-perforation ability of the multilayered concrete plates is dependent on both the target plate thickness and the projectile impact velocity. The variation range of the perforation ratio is 1-3.5 for concrete targets.

  7. Projectile Balloting Attributable to Gun Tube Curvature

    Directory of Open Access Journals (Sweden)

    Michael M. Chen

    2010-01-01

    Full Text Available Transverse motion of a projectile during launch is detrimental to firing accuracy, structural integrity, and/or on-board electronics performance of the projectile. One manifest contributing factor to the undesired motion is imperfect bore centerline straightness. This paper starts with the presentation of a deterministic barrel model that possesses both vertical and lateral deviations from centerline in accordance with measurement data, followed by a novel approach to simulating comprehensive barrel centerline variations for the investigation of projectile balloting^1 motions. A modern projectile was adopted for this study. In-bore projectile responses at various locations of the projectile while traveling through the simulated gun tubes were obtained. The balloting was evaluated in both time and frequency domains. Some statistical quantities and the significance were outlined.

  8. Sequential injection gas guns for accelerating projectiles

    Science.gov (United States)

    Lacy, Jeffrey M.; Chu, Henry S.; Novascone, Stephen R.

    2011-11-15

    Gas guns and methods for accelerating projectiles through such gas guns are described. More particularly, gas guns having a first injection port located proximate a breech end of a barrel and a second injection port located longitudinally between the first injection port and a muzzle end of the barrel are described. Additionally, modular gas guns that include a plurality of modules are described, wherein each module may include a barrel segment having one or more longitudinally spaced injection ports. Also, methods of accelerating a projectile through a gas gun, such as injecting a first pressurized gas into a barrel through a first injection port to accelerate the projectile and propel the projectile down the barrel past a second injection port and injecting a second pressurized gas into the barrel through the second injection port after passage of the projectile and to further accelerate the projectile are described.

  9. Projectile development for railguns using hypervelocity preacceleration

    Energy Technology Data Exchange (ETDEWEB)

    Susoeff, A.R.; Hawke, R.S. [Lawrence Livermore National Lab., CA (United States); Sauve, G.L. [EG and G Rocky Flats, Inc., Golden, CO (United States); Konrad, C.H. [Sandia National Labs., Albuquerque, NM (United States); Hickman, R.J. [Ktech Corp., Albuquerque, NM (United States)

    1991-02-01

    The STARFIRE Project is a joint Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) effort to achieve hypervelocity projectile launches up to 15 km/s. The apparatus used to achieve this goal is a three stage acceleration system made up of a two-stage light-gas gun (2SLGG) is used as a preaccelerator capable of injecting 2 gram projectiles at velocities of 6 km/s or more. Projectiles used in this environment are subject to many conditions. Some of these which effect projectile design include: acceleration loading, structural response, barrel condition and alignment. Development of a projectile to satisfy the programmatic requirements is underway. This report covers the evolution of design and fabrication for railgun projectiles from previous experience at LLNL to the replenished plasma armature and projectile now used on STARFIRE. Projectile design, development and fabrication methods which use off-the-shelf materials and standard techniques to meet the operational criteria of the experimental program are discussed in this paper. Initial work involving the design and fabrication of skirted projectiles, which are expected to further reduce interaction phenomena between the plasma armature and railgun barrel, is also described.

  10. Projectile development for railguns using hypervelocity preacceleration

    Energy Technology Data Exchange (ETDEWEB)

    Susoeff, A.R.; Hawke, R.S. (Lawrence Livermore National Lab., CA (United States)); Ang, J.A.; Asay, J.R.; Hall, C.A.; Konrad, C.H. (Sandia National Labs., Albuquerque, NM (United States)); Sauve, G.L. (EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant); Hickman, R.J. (Ktech Corp., Albuquerque, NM (United States))

    1992-03-20

    The STARFIRE Project is a joint Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) effort to achieve hypervelocity projectile launches up to 15 km/s. The apparatus used to achieve this goal is a three stage acceleration system made up of a two-stage light-gas gun (2SLGG) coupled to a railgun. The 2SLGG is used as a preaccelerator capable of injecting 2 gram projectiles at velocities of 6 km/s or more. Projectiles used in this environment are subject to many conditions. Some of these which effect projectile design include: acceleration loading, structural response, barrel condition and alignment. Development of a projectile to satisfy the programmatic requirements is underway. This report covers the evolution of design and fabrication for railgun projectiles from previous experiment at LLNL to the replenished plasma armature and projectile now used on STARFIRE. Projectile design, development and fabrication methods which use off-the-shelf materials and standard techniques to meet the operational criteria of the experimental program are discussed in this paper. Initial work involving the design and fabrication of skirted projectiles, which are expected to further reduce interaction phenomena between the plasma armature and railgun barrel, is also described.

  11. Projectile development for railguns using hypervelocity preacceleration

    Science.gov (United States)

    Susoeff, A. R.; Hawke, R. S.; Ang, J. A.; Asay, J. R.; Hall, C. A.; Konrad, C. H.; Sauve, G. L.

    1992-03-01

    The STARFIRE Project is a joint Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) effort to achieve hypervelocity projectile launches up to 15 km/s. The apparatus used to achieve this goal is a three stage acceleration system made up of a two-stage light-gas gun (2SLGG) coupled to a railgun. The 2SLGG is used as a preaccelerator capable of injecting 2 gram projectiles at velocities of 6 km/s or more. Projectiles used in this environment are subject to many conditions. Some of these which effect projectile design include acceleration loading, structural response, barrel condition and alignment. Development of a projectile to satisfy the programmatic requirements is underway. This report covers the evolution of design and fabrication for railgun projectiles from previous experimentation at LLNL to the replenished plasma armature and projectile now used on STARFIRE. Projectile design, development and fabrication methods which use off-the-shelf materials and standard techniques to meet the operational criteria of the experimental program are discussed in this paper. Initial work involving the design and fabrication of skirted projectiles, which are expected to further reduce interaction phenomena between the plasma armature and railgun barrel, is also described.

  12. REDUCED ENERGY CONSUMPTION THROUGH PROJECTILE BASED EXCAVATION

    Energy Technology Data Exchange (ETDEWEB)

    Mark Machina

    2002-10-12

    The Projectile Based Excavation (ProjEX) program has as its goal, the reduction of energy required for production mining and secondary breakage through the use of a projectile based excavation system. It depends on the development of a low cost family of projectiles that will penetrate and break up different types of ore/rock and a low cost electric launch system. The electric launch system will eliminate the need for high cost propellant investigated for similar concepts in the past. This document reports on the progress made in the program during the past quarter. It reports on projectile development and the development of the electric launch system design.

  13. Mathematical Model to Simulate the Trajectory Elements ofan Artillery Projectile Proof Shot

    Directory of Open Access Journals (Sweden)

    K.K. Chand

    2007-01-01

    Full Text Available In external ballistics of a conventional spin-stabilised artillery projectile, there are a numberof trajectory models developed for computing trajectory elements having varying degrees ofcomplexity. The present study attempts to propose a single mathematical model, viz., simplifiedpoint-mass/simple particle trajectory model to simulate the trajectory elements of a typical spin-stabilised flat-head artillery projectile proof shot. Due to difficulties in the projectile shape andsize, and the complicated nature of air resistance, an accurate mathematical prediction of thetrajectory is difficult. To simplify the computations, the governing equations of motion of theprojectile have been simplified and assumed that the projectile is a particle and the only forcesacting on the projectile are drag and gravity. With this model, trajectory elements have beengenerated and compared with experimental results obtained in the field test. The measuringinstrument used in this case is a Doppler radar.

  14. Scale effect of spherical projectiles for stabilization of oblique detonation waves

    Science.gov (United States)

    Maeda, S.; Sumiya, S.; Kasahara, J.; Matsuo, A.

    2015-03-01

    Oblique detonation waves (ODWs) were stabilized by launching a spherical projectile with 1.2-1.4 times the Chapman-Jouguet (C-J) velocity into detonable mixtures at rest. We used smaller projectiles (3.18 mm diameter) than those (4.76 mm diameter) in our previous studies and investigated the effect of the projectile scale on the stabilization of ODWs. We carried out high time resolution schlieren visualization using a high-speed camera. The detonable mixtures used were stoichiometric oxygen mixtures with acetylene, ethylene or hydrogen. They were diluted with argon with a 50 % volumetric fraction, and a dilute mixture containing 75 % argon was also tested for the acetylene/oxygen mixture. Here, we discuss the detonation stability in terms of the curvature effect arising from the three-dimensional nature of a stabilized ODW around a projectile. The curvature effect attenuated the detonation wave to below its C-J velocity in the vicinity of the projectile before the wave velocity asymptotically reached the C-J velocity in the far field. Our previous study showed that the propagation limit of the curvature effect is responsible for the stabilizing criticality of detonation waves. By obtaining detailed distributions of the wave propagation velocity and radius of curvature at the stabilizing criticality, we showed that the radius of curvature at the local minimum point of the wave propagation velocity represents the critical radius of curvature required for curved self-sustained detonation. In this study, we focused on this critical mode of the stabilized ODW for a small projectile (3.18 mm diameter). Distributions of the wave velocity and radius of curvature were obtained in the critical mode of the stabilized ODW. We compare these distributions with those for a larger projectile (4.76 mm diameter) and discuss the stabilizing criticality. For the small projectile, the observed combustion regimes had qualitatively the same trend for the initial pressure of the mixture

  15. Three-phase hypervelocity projectile launcher

    Science.gov (United States)

    Fugelso, L. Erik; Langner, Gerald C.; Burns, Kerry L.; Albright, James N.

    1994-01-01

    A hypervelocity projectile launcher for use in perforating borehole casings provides improved penetration into the surrounding rock structure. The launcher includes a first cylinder of explosive material that defines an axial air-filled cavity, a second cylinder of explosive material defining an axial frustum-shaped cavity abutting and axially aligned with the first cylinder. A pliant washer is located between and axially aligned with the first and second cylinders. The frustum shaped cavity is lined with a metal liner effective to form a projectile when the first and second cylinders are detonated. The washer forms a unique intermediate projectile in advance of the liner projectile and enables the liner projectile to further penetrate into and fracture the adjacent rock structure.

  16. A novel apoptosis correlated molecule: expression and characterization of protein Latcripin-1 from Lentinula edodes C(91-3).

    Science.gov (United States)

    Liu, Ben; Zhong, Mintao; Lun, Yongzhi; Wang, Xiaoli; Sun, Wenchang; Li, Xingyun; Ning, Anhong; Cao, Jing; Zhang, Wei; Liu, Lei; Huang, Min

    2012-01-01

    An apoptosis correlated molecule-protein Latcripin-1 of Lentinula edodes C(91-3)-was expressed and characterized in Pichia pastoris GS115. The total RNA was obtained from Lentinula edodes C(91-3). According to the transcriptome, the full-length gene of Latcripin-1 was isolated with 3'-Full Rapid Amplification of cDNA Ends (RACE) and 5'-Full RACE methods. The full-length gene was inserted into the secretory expression vector pPIC9K. The protein Latcripin-1 was expressed in Pichia pastoris GS115 and analyzed by Sodium Dodecylsulfonate Polyacrylate Gel Electrophoresis (SDS-PAGE) and Western blot. The Western blot showed that the protein was expressed successfully. The biological function of protein Latcripin-1 on A549 cells was studied with flow cytometry and the 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyl-tetrazolium Bromide (MTT) method. The toxic effect of protein Latcripin-1 was detected with the MTT method by co-culturing the characterized protein with chick embryo fibroblasts. The MTT assay results showed that there was a great difference between protein Latcripin-1 groups and the control group (p < 0.05). There was no toxic effect of the characterized protein on chick embryo fibroblasts. The flow cytometry showed that there was a significant difference between the protein groups of interest and the control group according to apoptosis function (p < 0.05). At the same time, cell ultrastructure observed by transmission electron microscopy supported the results of flow cytometry. The work demonstrates that protein Latcripin-1 can induce apoptosis of human lung cancer cells A549 and brings new insights into and advantages to finding anti-tumor proteins. PMID:22754362

  17. Plastic Guidance Fins for Long Rod Projectiles .

    Directory of Open Access Journals (Sweden)

    Mark L. Bundy

    1997-10-01

    Full Text Available Projectile tail fins on long rod kinetic energy (KE penetrators serve the same purpose as fletchings (feathers on an arrow, namely, they help align the projectile axis with its velocity vector. This reduces the projectile's yaw and hence reduces its aerodynamic drag. In addition, a low yaw angle at target impact helps to maximise the projectile's target penetration. It is typical for projectiles to exit the gun muzzle and enter free flight at some ndn-zero yaw angle. Aerodynamic forces acting on yawed tail fins create a stabilising torque about the projectile's centre of gravity (CG. This torque can be increased by making the fin material lighter. Most conventional long rod penetrators fired from high performance guns have tail fins made from aluminium. However, aluminium can undergo catastrophic oxidation (rapid burning in-bore. Coating aluminium with Al/sub 2/O/sub 3/ {hardcoat prevents ignition of the substrate, provided solid propellant grain impacts do not chip the brittle hardcoat off the surface. Plastic is lighter than aluminium and less exothermic when oxidized. Therefore, other factors aside, it is conceivable that plastic fins could increase projectile stability while incurring less thermal erosion than aluminium. However, thermal loads are not the only concern when considering plastic as an alternative tail fin material. The mechanical strength of plastic is also a critical factor. This paper discusses some of the successes and failures of plastic fins, at least relatively thin fins, for use as KE stabilisers.

  18. Non-invasive timing of gas gun projectiles with light detection and ranging

    International Nuclear Information System (INIS)

    We have developed a Light Detection and Ranging (LIDAR) diagnostic to track the position of a projectile inside of a gas gun launch tube in real-time. This capability permits the generation of precisely timed trigger pulses useful for triggering high-latency diagnostics such as a flash lamp-pumped laser. An initial feasibility test was performed using a 72 mm bore diameter single-stage gas gun routinely used for dynamic research at Los Alamos. A 655 nm pulsed diode laser operating at a pulse repetition rate of 100 kHz was used to interrogate the position of the moving projectile in real-time. The position of the projectile in the gun barrel was tracked over a distance of ∼ 3 meters prior to impact. The position record showed that the projectile moved at a velocity of 489 m/s prior to impacting the target. This velocity was in good agreement with independent measurements of the projectile velocity by photon Doppler velocimetry and timing of the passage of the projectile through optical marker beams positioned at the muzzle of the gun. The time-to-amplitude conversion electronics used enable the LIDAR data to be processed in real-time to generate trigger pulses at preset separations between the projectile and target.

  19. Structural design issues for electromagnetic projectiles

    International Nuclear Information System (INIS)

    This paper reports on many structural design issues associated with electromagnetic launch of projectiles which will respond to the same techniques as are used for conventional gun launch. The methods used to assess and manage the loads associated with the axial propulsive force (tapered sabots), which rapid propulsive rise time (dynamic finite element analysis), and with transverse balloting loads (coupled projectile/gun models) are interpreted for high velocity, electromagnetically accelerated projectiles. Finally some conclusions from these conventional interior ballistic technologies are offered for the EM designer

  20. Stability Criterion for a Finned Spinning Projectile

    Directory of Open Access Journals (Sweden)

    S. D. Naik

    2000-01-01

    Full Text Available The state-of-the-art in gun projectile technology has been used for the aerodynamic stabilisation.This approach is acceptable for guided and controlled rockets but the free-flight rockets suffer fromunacceptable dispersion. Sabot projectiles with both spin and fms developed during the last decadeneed careful analysis. In this study, the second method of Liapunov has been used to develop stability criterion for a projectile to be designed with small fins and is made to spin in the flight. This criterion is useful for the designer.

  1. AN EXPERIMENTAL TECHNIQUE TO MEASURE PROJECTILE DECELERATION HISTORY DURING NORMAL PENETRATION

    Institute of Scientific and Technical Information of China (English)

    INTO PLAIN; Liu Xiaohu; Liu Ji; Wang Cheng

    2000-01-01

    The present paper presents a new experimental method to measure the deceleration time his tory of projectiles penetrating into concrete in full-size test. The experiment can be carried out by using an onboard accelerometer to measure the projectile deceleration history and the data are transmitted to a ground recording system. With this experimental method, a series of tests on hemisphere-nose steel projectiles pene trating normally into plain concrete at the velocity region 150 - 400 m/s have been executed and the deceler ation histories obtained. The high frequency portion in the deceleration data has been investigated and proved to be the structure response of projectile. The characteristics of deceleration history have also been analyzed and discussed.

  2. REDUCED ENERGY CONSUMPTION THROUGH PROJECTILE BASED EXCAVATION

    Energy Technology Data Exchange (ETDEWEB)

    Mark Machina

    2003-06-06

    The Projectile Based Excavation (ProjEX) program has as its goal, the reduction of energy required for production mining and secondary breakage through the use of a projectile based excavation system. It depends on the development of a low cost family of projectiles that will penetrate and break up different types of ore/rock and a low cost electric launch system. The electric launch system will eliminate the need for high cost propellant considered for similar concepts in the past. This document reports on the program findings through the first two phases. It presents projectile design and experiment data and the preliminary design for electric launch system. Advanced Power Technologies, Inc., now BAE SYSTEMS Advanced Technologies, Inc., was forced to withdraw from the program with the loss of one of our principal mining partners, however, the experiments conducted suggest that the approach is feasible and can be made cost effective.

  3. Potential role of lncRNA cyp2c91-protein interactions on diseases of the immune system.

    Science.gov (United States)

    Suravajhala, Prashanth; Kogelman, Lisette J A; Mazzoni, Gianluca; Kadarmideen, Haja N

    2015-01-01

    With unprecedented increase in next generation sequencing technologies, there has been a persistent interest on transcript profiles of long non-coding RNAs (lncRNAs) and protein-coding genes forming an interaction network. Apart from protein-protein interaction (PPI), gene network models such as Weighted Gene Co-expression Network Analysis (WGCNA) are used to functionally annotate lncRNAs in identifying their potential disease associations. To address this, studies have led to characterizing transcript structures and understanding expression profiles mediating regulatory roles. In the current exploratory analysis, we show how a lncRNA - cyp2c91 contributes to the transcriptional regulation localized to cytoplasm thereby making refractory environment for transcription. By applying network methods and pathway analyses on genes related to a disease such as obesity and systemic lupus erythematosus, we show that we can gain deeper insight in biological processes such as the perturbances in immune system, and get a better understanding of the systems biology of diseases. PMID:26284111

  4. Potential role of lncRNA cyp2c91-protein interactions on diseases of the immune system

    Directory of Open Access Journals (Sweden)

    Prashanth eSuravajhala

    2015-07-01

    Full Text Available With unprecedented increase in next generation sequencing (NGS technologies, there has been a persistent interest on transcript profiles of long noncoding RNAs (lncRNAs and protein-coding genes forming an interaction network. Apart from protein-protein interaction (PPI, gene network models such as Weighted Gene Co-expression Network Analysis are used to functionally annotate lncRNAs in identifying their potential disease associations. To address this, studies have led to characterizing transcript structures and understanding expression profiles mediating regulatory roles. In the current exploratory analysis, we show how a lncRNA - cyp2c91 contributes to the transcriptional regulation localized to cytoplasm thereby making refractory environment for transcription. By applying network methods and pathway analyses on genes related to a disease such as obesity and systemic lupus erythematosus, we show that we can gain deeper insight in biological processes such as the perturbances in immune system, and get a better understanding of the systems biology of diseases.

  5. Pepper spray projectile/disperser for countering hostage and barricade situations

    Science.gov (United States)

    Kelly, Roy

    1997-01-01

    An improved less-than-lethal projectile for use in hostage, barricade and tactical assault situations has been developed. The projectile is launched from a standoff position and disperse the incapacitating agent oleoresin capsicum in the form of atomized droplets. A literature search followed by an experimental study were conducted of the mechanism of barrier defeat for various shaped projectiles against the targets of interest in this work: window glass, plasterboard and plywood. Some of the trade- offs between velocity, standoff, projectile shape and size, penetration, and residual energy were quantified. Analysis of the ballistic trajectory and recoil, together with calculations of he amount of pepper spray needed to incapacitate the occupants of a typical barricaded structure, indicated the suitability of using a fin stabilized projectile fired from a conventional 37 mm riot control gas gun. Two projectile designs were considered, manufactured and tested. The results of static tests to simulate target impact, together with live firing trials against a variety of targets, showed that rear ejection of the atomized spray was more reproducible and effective than nose ejection. The performance characteristics of the finalized design were investigated in trials using the standard barrier for testing barrier penetrating tear gas agents as defined by the National Institute of Justice.

  6. Three Dimensional CAPP Technology of Projectile Based on MBD

    Directory of Open Access Journals (Sweden)

    Hongzhi Zhao

    2013-07-01

    Full Text Available This study aims at the research goal of three-dimensional digital process design of projectile, which adopts three-dimensional computer-aided process design technology based on MBD and uses MBD to conduct parametric modeling of projectile that can reduce the input of projectile’s process information and data conversion and produce reasonable, feasible and three-dimensional projectile manufacturing process to realize paperless three-dimensional process design of projectile. The application of three-dimensional computer-assisted process design technology of projectile based on model definition can shorten the design cycle of projectile, thus improving rapid manufacturing capacity of product and reducing cost.

  7. Penetration Experiments with 6061-T6511 Aluminum Targets and Spherical-Nose Steel Projectiles at Striking Velocities Between 0.5 and 3.0 km/s

    Energy Technology Data Exchange (ETDEWEB)

    Forrestal, M.J.; Piekutowski, A.J.

    1999-02-04

    We conducted depth of penetration experiments with 7.11-mm-diameter, 74.7-mm-long, spherical-nose, 4340 steel projectiles launched into 250-mm-diameter, 6061-T6511 aluminum targets. To show the effect of projectile strength, we used projectiles that had average Rockwell harnesses of R{sub c} = 36.6, 39.5, and 46.2. A powder gun and two-stage, light-gas guns launched the 0.023 kg projectiles at striking velocities between 0.5 and 3.0 km/s. Post-test radiographs of the targets showed three response regions as striking velocities increased: (1) the projectiles remained visibly undeformed, (2) the projectiles permanently deformed without erosion, and (3) the projectiles eroded and lost mass. To show the effect of projectile strength, we compared depth-of-penetration data as a function of striking velocity for spherical-nose rods with three Rockwell harnesses at striking velocities ranging from 0.5 to 3.0 km/s. To show the effect of nose shape, we compared penetration data for the spherical-nose projectiles with previously published data for ogive-nose projectiles.

  8. Isoscaling of projectile-like fragments

    Institute of Scientific and Technical Information of China (English)

    Zhong Chen; Chen Jin-Hui; Guo Wei; Ma Chun-Wang; Ma Guo-Liang; Su Qian-Min; Yan Ting-Zhi; Zuo Jia-Xu; Ma Yu-Gang; Fang De-Qing; Cai Xiang-Zhou; Chen Jin-Gen; Shen Wen-Qing; Tian Wen-Dong; Wang Kun; Wei Yi-Bin

    2006-01-01

    In this paper, the isotopic and isotonic distributions of projectile fragmentation products have been simulated by a modified statistical abrasion-ablation model and the isoscaling behaviour of projectile-like fragments has been discussed. The isoscaling parameters α andβ have been extracted respectively, for hot fragments before evaporation and cold fragments after evaporation. It looks that the evaporation has stronger effect on α than β. For cold fragments,a monotonic increase of α and |β| with the increase of Z and N is observed. The relation between isoscaling parameter and the change of isospin content is discussed.

  9. Sputtering of indium using polyatomic projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Samartsev, A.V.; Wucher, A

    2004-06-15

    We have investigated the emission of neutral and charged particles from a polycrystalline indium surface under bombardment with Au, Au{sub 2}, Au{sub 3}, Au{sub 5} and AuCs{sub 2} projectiles with energies between 5 and 10 keV. Sputtered neutral species were postionized by means of saturated single photon ionization, thus characterizing the respective partial sputtering yields. The ionization probability of the emitted species was addressed by measuring the respective secondary ion signals under the same experimental conditions. It is seen that the relative cluster yields are enhanced under polyatomic projectile bombardment, while the ionization probability of In atoms seems to be largely unaffected.

  10. Minimum and terminal velocities in projectile motion

    OpenAIRE

    Miranda, E. N.; Nikolskaya, S.; Riba, R.

    2012-01-01

    The motion of a projectile with horizontal initial velocity V0, moving under the action of the gravitational field and a drag force is studied analytically. As it is well known, the projectile reaches a terminal velocity Vterm. There is a curious result concerning the minimum speed Vmin; it turns out that the minimum velocity is lower than the terminal one if V0 > Vterm and is lower than the initial one if V0 < Vterm. These results show that the velocity is not a monotonous function. If the i...

  11. Dynamic effects of interaction of composite projectiles with targets

    Energy Technology Data Exchange (ETDEWEB)

    Zakharov, V. M. [Scientific Research Institute of Applied Mathematics and Mechanics of Tomsk State University, 36, Lenin Avenue, Tomsk, 634050 (Russian Federation)

    2016-01-15

    The process of high-speed impact of projectiles against targets of finite thickness is experimentally investigated. Medium-hard steel plates are used as targets. The objective of this research is to carry out a comparative analysis of dynamic effects of interaction of various types of projectiles with targets, such as characteristics of destruction of the target, the state of the projectile behind the target, and particularities of the after-penetration stream of fragments after the target has been pierced. The projectiles are made of composites on the basis of tungsten carbide obtained by caking and the SHS-technology. To compare effectiveness of composite projectiles steel projectiles are used. Their effectiveness was estimated in terms of the ballistic limit. High density projectiles obtained by means of the SHS-technology are shown to produce results comparable in terms of the ballistic limit with high-strength projectiles that contain tungsten received by caking.

  12. Fatal lawn mower related projectile injury

    DEFF Research Database (Denmark)

    Colville-Ebeling, Bonnie; Lynnerup, Niels; Banner, Jytte

    2014-01-01

    operator or a bystander is impacted by an object mobilized from the grass by the rotating mower blades. This type of injury often leaves only modest external trauma, which increases the risk of overlooking an entry wound. In this paper we present a case of a fatal lawn mower related projectile injury which...

  13. Speed, Acceleration, Chameleons and Cherry Pit Projectiles

    Science.gov (United States)

    Planinsic, Gorazd; Likar, Andrej

    2012-01-01

    The paper describes the mechanics of cherry pit projectiles and ends with showing the similarity between cherry pit launching and chameleon tongue projecting mechanisms. The whole story is written as an investigation, following steps that resemble those typically taken by scientists and can therefore serve as an illustration of scientific…

  14. Three Dimensional CAPP Technology of Projectile Based on MBD

    OpenAIRE

    Hongzhi Zhao; Yingai Piao; Xiaoyong Zhu

    2013-01-01

    This study aims at the research goal of three-dimensional digital process design of projectile, which adopts three-dimensional computer-aided process design technology based on MBD and uses MBD to conduct parametric modeling of projectile that can reduce the input of projectile’s process information and data conversion and produce reasonable, feasible and three-dimensional projectile manufacturing process to realize paperless three-dimensional process design of projectile. The application of ...

  15. A note on stability of motion of a projectile

    Indian Academy of Sciences (India)

    S D Naik

    2001-08-01

    A projectile is stabilised using either gyroscopic or aerodynamic stability. But subcalibre projectiles with sabot have both spin and fins. Separate stability criteria are researched generally for each type of projectile. In this paper a stability criterion which can be used for all such bodies has been developed through the Liapunov second method.

  16. Experimental investigation on underwater trajectory deviation of high-speed projectile with different nose shapes

    Science.gov (United States)

    Zhang, Wei; Huang, Wei; Gao, Yubo; Qi, Yafei; Hypervelocity Impact Research Center Team

    2015-06-01

    Laboratory-scaled oblique water entry experiments for the trajectory stability in the water column have been performed with four different nosed-projectiles at a range of velocities from 20m /s to 250 m /s . The slender projectiles are designed with flat, ogival, hemi-sperical, truncated-ogival noses to make comparisons on the trajectory deviation when they are launched at vertical and oblique impact angles (0°~25°). Two high-speed cameras that are positioned orthogonal to each other and normal to the column are employed to capture the entire process of projectiles' penetration. From the experimental results, the sequential images in two planes are presented to compare the trajectory deviation of different impact tests and the 3D trajectory models are extracted based on the location recorded by cameras. Considering the effect influenced by the impact velocities and noses of projectiles, it merited concluded that trajectory deviation is affected from most by impact angle, and least by impact velocities. Additionally, ogival projectiles tend to be more sensitive to oblique angle and experienced the largest attitude changing. National Natural Science Foundation of China (NO.: 11372088).

  17. Minimum and terminal velocities in projectile motion

    CERN Document Server

    Miranda, E N; Riba, R

    2012-01-01

    The motion of a projectile with horizontal initial velocity V0, moving under the action of the gravitational field and a drag force is studied analytically. As it is well known, the projectile reaches a terminal velocity Vterm. There is a curious result concerning the minimum speed Vmin; it turns out that the minimum velocity is lower than the terminal one if V0 > Vterm and is lower than the initial one if V0 < Vterm. These results show that the velocity is not a monotonous function. If the initial speed is not horizontal, there is an angle range where the velocity shows the same behavior mentioned previously. Out of that range, the volocity is a monotonous function. These results come out from numerical simulations.

  18. The projectile fragment separator FRS at GSI

    International Nuclear Information System (INIS)

    The new accelerator facilities at GSI, which are scheduled for operation by the beginning of 1990, will extend heavy-ion research and applications to relativistic energies. The projectile fragment separator FRS will produce and separate in-flight radioactive beams of all elements up to uranium. The combination of the FRS with the storage and cooler ring ESR opens a new area of experiments. The FRS project and some of the planned experiments are presented in this contribution. (orig.)

  19. The Envelope of Projectile Trajectories in Midair

    CERN Document Server

    Chudinov, P

    2005-01-01

    A classic problem of the motion of a point mass (projectile) thrown at an angle to the horizon is reviewed. The air drag force is taken into account with the drag factor assumed to be constant. Analytic approach is used for investigation. Simple analytical formulas are used for the constructing the envelope of the family of the point mass trajectories. The equation of envelope is applied for determination of maximum range of flight. The motion of a baseball is presented as an example.

  20. Evaluating simulant materials for understanding cranial backspatter from a ballistic projectile.

    Science.gov (United States)

    Das, Raj; Collins, Alistair; Verma, Anurag; Fernandez, Justin; Taylor, Michael

    2015-05-01

    In cranial wounds resulting from a gunshot, the study of backspatter patterns can provide information about the actual incidents by linking material to surrounding objects. This study investigates the physics of backspatter from a high-speed projectile impact and evaluates a range of simulant materials using impact tests. Next, we evaluate a mesh-free method called smoothed particle hydrodynamics (SPH) to model the splashing mechanism during backspatter. The study has shown that a projectile impact causes fragmentation at the impact site, while transferring momentum to fragmented particles. The particles travel along the path of least resistance, leading to partial material movement in the reverse direction of the projectile motion causing backspatter. Medium-density fiberboard is a better simulant for a human skull than polycarbonate, and lorica leather is a better simulant for a human skin than natural rubber. SPH is an effective numerical method for modeling the high-speed impact fracture and fragmentations. PMID:25739515

  1. Experimental Study and Numerical Simulation of Hypervelocity Projectile Impact on Double-Wall Structure

    Institute of Scientific and Technical Information of China (English)

    陈沿海; 张庆明; 黄风雷

    2004-01-01

    Tests of hypervelocity projectile impact on double-wall structure were performed with the front wall ranging from 0.5 mm to 2.0 mm thick and different impact velocities. Smooth particle hydrodynamics (SPH) code in LS-DYNA was employed for the simulation of hypervelocity impact on the double-wall structure. By using elementary shock wave theory, the experimental results above are analyzed. The analysis can provide an explanation for the penetration mechanism of hypervelocity projectile impact on double-wall structure about the effect of front wall thickness and impact velocity.

  2. Determination of local TNT density in cannon projectile casing by γ ray non-destructive inspection

    International Nuclear Information System (INIS)

    The concept of the equivalent physical absorption thickness rp was presented and defined. Irradiated portion of the cannon projectile by collimated γ ray is a pillar having streamline cone. The authors calculated the rp values of the pillar which is filled up by medium materials, such as TNT, H2O and air. The practical formula was deduced for testing local TNT density in cannon projectile casing. The densities of the sections with a shape like a streamline pillar in casing, which was filled up with different materials in turn, have been determined experimentally

  3. Forensic and clinical issues in the use of frangible projectile.

    Science.gov (United States)

    Komenda, Jan; Hejna, Petr; Rydlo, Martin; Novák, Miroslav; Krajsa, Jan; Racek, František; Rejtar, Pavel; Jedlička, Luděk

    2013-08-01

    Frangible projectiles for firearms, which break apart on impact, are mainly used by law enforcement agencies for training purposes, but can also be used for police interventions. Apart from the usual absence of lead in the projectiles, the main advantage of using frangible projectiles is the reduced risk of ricochet after impact with a hard target. This article describes the design and function of frangible projectiles, and describes gunshot wounds caused by ultra-frangible projectiles which fragment after penetration of soft tissues. Shooting experiments performed by the authors confirmed that differences in the geometry and technology of frangible projectiles can significantly modify their wounding effects. Some frangible projectiles have minimal wounding effects because they remain compact after penetration of soft tissues, comparable to standard fully jacketed projectiles. However, a number of ultra-frangible projectiles disintegrate into very small fragments after impact with a soft tissue substitute. In shooting experiments, we found that the terminal behavior of selected ultra-frangible projectiles was similar in a block of ballistic gel and the soft tissues of the hind leg of a pig, except that the degree of disintegration was less in the gel. PMID:23910864

  4. Study on Overall Concept Planning of Terminal Correction Mortar Projectiles

    Institute of Scientific and Technical Information of China (English)

    XU Jin-xiang

    2008-01-01

    The system composition, the operational principle of terminal correction mortar projectiles (TCMP) and the concept planning design of TCMP are researched in this paper. An overall design and aerodynamic configuration layout for TCMP are made in this paper, and its aerodynamic coefficients are calculated by using computational fluid dynamics (CFD) software. Test results of TCMP simulated ballistic projectiles indicate the designed TCMP can satisfy the interior ballistic demand and has a fine flight stability. The drag coefficients identified from the radar velocity-time data are in accord with the CFD computed results. According to the exposure frequency of the ground laser designator, a four-quadrant impulse correction scheme and a high exposure frequency impulse correction scheme are brought. The latter can calculate the target azimuth angle by counting the times of the facula passing through one quadrant. Simulation results also show that the guidance precision of the velocity pursuit is higher than that of the body pursuit, and the detector axis is less circuitous. Researches on the typical trajectory indicate that the terminal impulse correction can improve the hit precision of TCMP remarkably.

  5. Hign-speed penetration of projectile with cavitator into sand

    Science.gov (United States)

    Daurskikh, Anna; Veldanov, Vladislav

    2011-06-01

    Cavitators are used in underwater projectiles design to form a cavern in which projectile could move with no or significantly reduced drag. An investigation of possible application of this structural element for penetration into porous media was conducted. High-speed impact of a conical-shaped head projectile with cavitator was studied in terms of its influence on penetration capacity and projectile stability in sand for impact velocity about 1500 m/s. Cavitators were manufactured of steel with different strength moduli, and thus two penetration regimes (with eroding/non-eroding cavitator) were compared. Numerical simulations showing wave propagation in target and projectile were performed in AUTODYN with Johnson-Cook model for projectile and granular model for sand.

  6. Penetration of Granular Projectiles into a Water Target

    OpenAIRE

    González-Gutiérrez, Jorge; J. L. Carrillo-Estrada; Ruiz-Suárez, J. C.

    2014-01-01

    The penetration of low-speed projectiles into a water target has been studied in the last several years to understand the physics behind the formation and collapse of cavities. In such studies, the projectiles employed were solid bodies or liquid drops. Here we report similar impact experiments using granular projectiles, with the aim to investigate how the morphology of the cavities is determined by the balance between the dynamic pressure exerted by the fluid and the cohesive strength of th...

  7. New projectiles: multicharged metal clusters and biopolymers

    International Nuclear Information System (INIS)

    Metal clusters and molecules are the one mean to realize simultaneous impacts of several atoms on a reduced surface(∼100A). The interaction characteristics is the non-linearity of energy deposition; the perturbation that the cluster produces, is above than the sum of the perturbation induced by its components, taken separately. The purpose of ORION project is to accelerate these new projectiles at ORSAY Tandem. The considered mass range is from 100 Daltons to 100 000 Daltons and energy range from MeV to GeV

  8. Projectile development for railguns using hypervelocity preacceleration. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Susoeff, A.R.; Hawke, R.S. [Lawrence Livermore National Lab., CA (United States); Ang, J.A.; Asay, J.R.; Hall, C.A.; Konrad, C.H. [Sandia National Labs., Albuquerque, NM (United States); Sauve, G.L. [EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant; Hickman, R.J. [Ktech Corp., Albuquerque, NM (United States)

    1992-03-20

    The STARFIRE Project is a joint Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) effort to achieve hypervelocity projectile launches up to 15 km/s. The apparatus used to achieve this goal is a three stage acceleration system made up of a two-stage light-gas gun (2SLGG) coupled to a railgun. The 2SLGG is used as a preaccelerator capable of injecting 2 gram projectiles at velocities of 6 km/s or more. Projectiles used in this environment are subject to many conditions. Some of these which effect projectile design include: acceleration loading, structural response, barrel condition and alignment. Development of a projectile to satisfy the programmatic requirements is underway. This report covers the evolution of design and fabrication for railgun projectiles from previous experiment at LLNL to the replenished plasma armature and projectile now used on STARFIRE. Projectile design, development and fabrication methods which use off-the-shelf materials and standard techniques to meet the operational criteria of the experimental program are discussed in this paper. Initial work involving the design and fabrication of skirted projectiles, which are expected to further reduce interaction phenomena between the plasma armature and railgun barrel, is also described.

  9. Stability analyses of the mass abrasive projectile high-speed penetrating into a concrete target Part III: Terminal ballistic trajectory analyses

    Science.gov (United States)

    Wu, H.; Chen, X. W.; Fang, Q.; Kong, X. Z.; He, L. L.

    2015-08-01

    During the high-speed penetration of projectiles into concrete targets (the impact velocity ranges from 1.0 to 1.5 km/s), important factors such as the incident oblique and attacking angles, as well as the asymmetric abrasions of the projectile nose induced by the target-projectile interactions, may lead to obvious deviation of the terminal ballistic trajectory and reduction of the penetration efficiency. Based on the engineering model for the mass loss and nose-blunting of ogive-nosed projectiles established, by using the Differential Area Force Law (DAFL) method and semi-empirical resistance function, a finite differential approach was programmed (PENTRA2D) for predicting the terminal ballistic trajectory of mass abrasive high-speed projectiles penetrating into concrete targets. It accounts for the free-surface effects on the drag force acting on the projectile, which are attributed to the oblique and attacking angles, as well as the asymmetric nose abrasion of the projectile. Its validation on the prediction of curvilinear trajectories of non-normal high-speed penetrators into concrete targets is verified by comparison with available test data. Relevant parametric influential analyses show that the most influential factor for the stability of terminal ballistic trajectories is the attacking angle, followed by the oblique angle, the discrepancy of asymmetric nose abrasion, and the location of mass center of projectile. The terminal ballistic trajectory deviations are aggravated as the above four parameters increase.

  10. Mass stabilized projectile designs for electromagnetic launch

    International Nuclear Information System (INIS)

    A dual density Rodman cone, with l/d = 7, has been found to be attractive for electromagnetic launch and may have adequate terminal ballistic performance. Stable flight is achieved from the correct distribution of mass within the projectile body. The design provides some flexibility for the armature in that all the armature mass is used for aerodynamic stability. Furthermore, the acceleration can be supported by a simple one-piece armature. A bore rider, which is less than 10% of the total mass, is needed for in-bore stability and structural support at the tungsten/aluminum interface. Work to date has focused on small caliber applications, but substantial gains can be achieved when the bore size is increased to cannon caliber. General design principles are presented for a mass stabilized projectile. This paper addresses nearly all aspects of launch, flight, and terminal effects as a function of bore size. Flight and terminal effects are computed from curve fits to existing experimental data

  11. Penetration of projectiles into granular targets

    Science.gov (United States)

    Ruiz-Suárez, J. C.

    2013-06-01

    Energetic collisions of subatomic particles with fixed or moving targets have been very valuable to penetrate into the mysteries of nature. But the mysteries are quite intriguing when projectiles and targets are macroscopically immense. We know that countless debris wandering in space impacted (and still do) large asteroids, moons and planets; and that millions of craters on their surfaces are traces of such collisions. By classifying and studying the morphology of such craters, geologists and astrophysicists obtain important clues to understand the origin and evolution of the Solar System. This review surveys knowledge about crater phenomena in the planetary science context, avoiding detailed descriptions already found in excellent papers on the subject. Then, it examines the most important results reported in the literature related to impact and penetration phenomena in granular targets obtained by doing simple experiments. The main goal is to discern whether both schools, one that takes into account the right ingredients (planetary bodies and very high energies) but cannot physically reproduce the collisions, and the other that easily carries out the collisions but uses laboratory ingredients (small projectiles and low energies), can arrive at a synergistic intersection point.

  12. Locating the source of projectile fluid droplets

    CERN Document Server

    Varney, Christopher R

    2011-01-01

    The ballistically ill-posed projectile problem of finding source height from spattered droplets of viscous fluid is a longstanding obstacle to accident reconstruction and crime scene analysis. It is widely known how to infer the impact angle of droplets on a surface from the elongation of their impact profiles. Due to missing velocity information, however, finding the height of origin from impact position and angle of individual drops is not possible. Turning to aggregate statistics of the spatter and basic equations of projectile motion familiar to physics students, we introduce a reciprocal correlation plot that is effective when the polar angle of launch is concentrated in a narrow range. The horizontal plot coordinate is twice the reciprocal of impact distance, and the vertical coordinate depends on the orientation of the spattered surface; for a level surface this is the tangent of impact angle. In all cases one infers source height as the slope of data points in the reciprocal correlation plot. Such plo...

  13. Cold fusion reactions using neutron-rich projectiles

    International Nuclear Information System (INIS)

    This paper studies the formation cross-sections of super heavy (SH) nuclei in some cold fusion reactions of radioactive neutron-rich projectiles with double-magic 208Pb target. In this study, the cross-sections of capture, fusion and evaporation residues in one- and two-neutron (1n and 2n) channels are calculated by using neutron-rich Fe, Ni and Zn projectiles are compared to the cross-sections calculated using stable Fe, Ni and Zn projectiles. The heights of fusion barrier and their positions in all reactions considered in this study are also compared to the heights and positions calculated using the estimation method proposed by Dutt and Puri. For cold fusion reactions with stable Fe, Ni and Zn projectiles, the heights of fusion barrier and the cross-sections of evaporation residues in 1n and 2n channels are compared to their corresponding experimental data. In general, for reactions using projectiles with the same proton number, the neutron-rich projectile is found to yield relatively-heavier mass of SH nucleus and larger evaporation residue cross-section, compared to those of the corresponding stable projectiles. However, in certain reactions, the cross-sections of neutron-rich projectile can be slightly larger or slightly smaller than that of the corresponding stable projectile. This behavior is highly affected by the charge of projectile and the fission barrier of the formed compound nucleus (CN). In addition, the 292114 is found to be the heaviest compound nucleus formed in cold fusion reaction by using neutron-rich nuclei as the projectile, but the cross-section of evaporation residue in one-neutron channel is still around few pico barns (pb). (author)

  14. Polymer Recovery from Auto Shredder Residue by Projectile Separation Method

    Directory of Open Access Journals (Sweden)

    Dong Yang Wu

    2012-04-01

    Full Text Available The number of vehicles on the road has been increasing at an enormous rate over the last decade. By 2015, the number of vehicles that reach the end of their life will be close to a million per year in Australia. Most metallic parts of the vehicle can be recycled but the plastic components and components of other materials are normally shredded and disposed in landfills. As more vehicles are using composite materials, the percentage of materials sent to landfill is alarming. This paper reviews existing polymer recycling techniques for End-of-Life Vehicles (ELVs and proposes a more efficient electrostatic based projectile separation method. The test rig is at the preliminary stage of development and initial outcomes are promising.

  15. Extraordinary energy production after collision of metallic projectile with solid target

    International Nuclear Information System (INIS)

    Production of additional energy in collision of metallic projectile with solid target is considered. It is shown that when the projectile speed exceeds certain threshold, the heat energy after collision may sufficiently exceed the kinetic energy of the projectile

  16. Corrected Launch Speed for a Projectile Motion Laboratory

    Science.gov (United States)

    Sanders, Justin M.; Boleman, Michael W.

    2013-01-01

    At our university, students in introductory physics classes perform a laboratory exercise to measure the range of a projectile fired at an assigned angle. A set of photogates is used to determine the initial velocity of the projectile (the launch velocity). We noticed a systematic deviation between the experimentally measured range and the range…

  17. Development of a numerical model for the ballistic penetration of Fackler gelatine by small calibre projectiles

    Science.gov (United States)

    Gilson, L.; Rabet, L.; Imad, A.; Kakogiannis, D.; Coghe, F.

    2016-03-01

    Among the different material surrogates used to study the effect of small calibre projectiles on the human body, ballistic gelatine is one of the most commonly used because of its specific material properties. For many applications, numerical simulations of this material could give an important added value to understand the different phenomena observed during ballistic testing. However, the material response of gelatine is highly non-linear and complex. Recent developments in this field are available in the literature. Experimental and numerical data on the impact of rigid steel spheres in gelatine available in the literature were considered as a basis for the selection of the best model for further work. For this a comparison of two models for Fackler gelatine has been made. The selected model is afterwards exploited for a real threat consisting of two types of ammunitions: 9 mm and .44 Magnum calibre projectiles. A high-speed camera and a pressure sensor were used in order to measure the velocity decay of the projectiles and the pressure at a given location in the gelatine during penetration of the projectile. The observed instability of the 9 mm bullets was also studied. Four numerical models were developed and solved with LS-DYNA and compared with the experimental data. Good agreement was obtained between the models and the experiments validating the selected gelatine model for future use.

  18. Development of a numerical model for the ballistic penetration of Fackler gelatine by small calibre projectiles

    Science.gov (United States)

    Gilson, L.; Rabet, L.; Imad, A.; Kakogiannis, D.; Coghe, F.

    2016-05-01

    Among the different material surrogates used to study the effect of small calibre projectiles on the human body, ballistic gelatine is one of the most commonly used because of its specific material properties. For many applications, numerical simulations of this material could give an important added value to understand the different phenomena observed during ballistic testing. However, the material response of gelatine is highly non-linear and complex. Recent developments in this field are available in the literature. Experimental and numerical data on the impact of rigid steel spheres in gelatine available in the literature were considered as a basis for the selection of the best model for further work. For this a comparison of two models for Fackler gelatine has been made. The selected model is afterwards exploited for a real threat consisting of two types of ammunitions: 9 mm and .44 Magnum calibre projectiles. A high-speed camera and a pressure sensor were used in order to measure the velocity decay of the projectiles and the pressure at a given location in the gelatine during penetration of the projectile. The observed instability of the 9 mm bullets was also studied. Four numerical models were developed and solved with LS-DYNA and compared with the experimental data. Good agreement was obtained between the models and the experiments validating the selected gelatine model for future use.

  19. Role of projectile coherence in atomic fragmentation processes

    International Nuclear Information System (INIS)

    Very surprising discrepancies between experiment and fully quantum-mechanical calculations were reported in fully differential cross sections (FDCS) for single target ionization by ion impact. Even more surprising, semi-classical approaches, treating the projectile-target nucleus interaction classically, good agreement with the data was achieved. This raised the question whether the fully quantum-mechanical calculations share a fundamental, so far overlooked problem. One feature which all of them have in common is that they assume a completely de-localized projectile wave, a coherent projectile beam. This is a rather unrealistic assumption for fast ion impact since there the projectile wave packet always has a width which is negligible compared to the size of the target atom. We have performed a series of experiments which demonstrate that cross sections for atomic fragmentation processes can sensitively depend on the projectile coherence properties. In the first set of experiments inelastic scattering of protons from H2, was investigated

  20. Isospin dependent multifragmentation of relativistic projectiles

    CERN Document Server

    Ogul, R; Atav, U; Buyukcizmeci, N; Mishustin, I N; Adrich, P; Aumann, T; Bacri, C O; Barczyk, T; Bassini, R; Bianchin, S; Boiano, C; Boudard, A; Brzychczyk, J; Chbihi, A; Cibor, J; Czech, B; De Napoli, M; Ducret, J -E; Emling, H; Frankland, J D; Hellstrom, M; Henzlova, D; Imme, G; Iori, I; Johansson, H; Kezzar, K; Lafriakh, A; Le Fèvre, A; Gentil, E Le; Leifels, Y; Luhning, J; Lukasik, J; Lynch, W G; Lynen, U; Majka, Z; Mocko, M; Muller, W F J; Mykulyak, A; Orth, H; Otte, A N; Palit, R; Pawlowski, P; Pullia, A; Raciti, G; Rapisarda, E; Sann, H; Schwarz, C; Sfienti, C; Simon, H; Summerer, K; Trautmann, W; Tsang, M B; Verde, G; Volant, C; Wallace, M; Weick, H; Wiechula, J; Wieloch, A; Zwieglinski, B

    2010-01-01

    The N/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at SIS. Stable and radioactive Sn and La beams with an incident energy of 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. For the interpretation of the data, calculations with the Statistical Multifragmentation Model for a properly chosen ensemble of excited sources were performed. The parameters of the ensemble, representing the variety of excited spectator nuclei expected in a participant-spectator scenario, are determined empirically by searching for an optimum reproduction of the measured fragment charge distributions and correlations. An overall very good agreement is obtained. The possible modification of the liquid-drop parameters of the fragment description in the hot freeze-out environment is studied, and a significant reduction of the symmetry-term coefficient is found necessary to reproduce the mean neutron-to-proton ratios /Z an...

  1. Influence of projectile breakup on complete fusion

    Indian Academy of Sciences (India)

    A Mukherjee; M K Pradhan

    2010-07-01

    Complete fusion excitation functions for 11,10B+159Tb and 6,7Li+159Tb have been reported at energies around the respective Coulomb barriers. The measurements show significant suppression of complete fusion cross-sections at energies above the barrier for 10B+159Tb and 6,7Li+159Tb reactions, when compared to those for 11B+159Tb. The comparison shows that the extent of suppression of complete fusion cross-sections is correlated with the -separation energies of the projectiles. Also, the measured incomplete fusion cross-sections show that the -particle emanating channel is the favoured incomplete fusion process. Inclusive measurement of the -particles produced in 6Li+159Tb reaction has been carried out. Preliminary CDCC calculations carried out to estimate the - yield following 6Li breaking up into + fail to explain the measured -yield. Transfer processes seem to be important contributors.

  2. Projectile impact Hugoniot parameters for selected materials

    Energy Technology Data Exchange (ETDEWEB)

    Vigil, M G

    1989-08-01

    The Rankine Hugoniot equation relating the conversion of momentum across a shock front and the empirical relationship for shock velocity as a function of particle velocity are used to calculate the impact pressures for selected materials. The shock velocity and particle velocities are then calculated as a function of impact pressures. The calculated data are graphically presented sets of three figures for the selected materials as follows: Impact pressure as a function of impact velocity, impact pressure as a function of particle velocity, impact pressure as a function of shock velocity. Given the projectile impact velocity and material Hugoniot information, this graphical representation of the data allows for a fast approximation of the impact pressure particle velocity, and shock velocity in the target material. 9 refs., 1 fig., 3 tabs.

  3. A study of the penetration of projectiles into marine sediments

    International Nuclear Information System (INIS)

    The work described in this document consists of three main parts: - Application, after having reviewed calculation methods and known codes, of a dynamic plasticity model based on the upper bound-method (with dissipated energy calculations by plastic deformations). The soil model used for this calculation is the Cambridge Clay Model. - Carrying out a programme of tests with instrumented small scale penetrators in centrifuge on a consolidated clay-target. The trials are done under 50 g, with projectiles, fired with an airgun at high impact velocity (50 m/s). The penetrators' instrumentation consists of either measuring acceleration, or tip force with strain gauges. - The mounting of a small instrumented penetrator for shallow water depth experimentations, with an accelerometer, and a local cell for tip resistance. A rapid electronic data acquisition system has been developed for these experimentations. The preliminary tests are done in a large tank filled with clay. The geotechnical characteristics of the clay are perfectly controlled. The tests performed under these conditions have shown the following observations: the rapid electronic data acquisition system works perfectly and could be used as a basic component for a deep water instrumentated penetrator; the results, obtained in these particular test conditions, are in a perfect agreement with the predictions of the model developed in the frame of this contract

  4. NUMERICAL SIMULATION FOR FORMED PROJECTILE OF DEPLETED URANIUM ALLOY

    Institute of Scientific and Technical Information of China (English)

    宋顺成; 高平; 才鸿年

    2003-01-01

    The numerical simulation for forming projectile of depleted uranium alloy with the SPH ( Smooth Particle Hydrodynamic ) algorithm was presented. In the computations the artificial pressures of detonation were used, i. e. , the spatial distribution and time distribution were given artificially. To describe the deformed behaviors of the depleted uranium alloy under high pressure and high strain rate, the Johnson-Cook model of materials was introduced. From the numerical simulation the formed projectile velocity,projectile geometry and the minimum of the height of detonation are obtained.

  5. Comparison Among Depths of Penetration of Different Targets Subjected to Rigid Projectile Impact

    Institute of Scientific and Technical Information of China (English)

    LI Jicheng; CHEN Xiaowei

    2008-01-01

    The ratios of depth of penetration (DOP) of different targets under the same penetration condition was investigated according to the dimensionless formula of DOP of different targets penetrated by a non-deformable projectile.Results show that various targets may be equivalent to each other.The applicable range of the equivalence and the feasibility of targets substitution were discussed by integrating the available test data.

  6. Study of momentum distributions for projectile fragments of 22Ne and 28Si nuclei in collisions with emulsion

    International Nuclear Information System (INIS)

    The charge and mass yield curves and the momentum distributions of the projectile fragments produced in the interactions of 4.1 A GeV/c 22Ne and 4.5 A GeV/c 28Si with emulsion have been studied. The overall charge distributions of the projectile fragments resulting from these interactions are presented. The dependence of the mass yield distributions of the projectile fragments on the impact parameter has been tested. The momentum distributions for the considered reactions have been investigated by two methods. First, the projected momentum distributions in the plane of the microscope have been achieved by fitting the projected angular distributions to gaussian ones. It has been found that the width of the distribution changes with the charge of the projectile fragment and it decreases with the increase of the projectile fragment charge. Secondly, the transverse momentum distributions have been compared with previous studies. The momentum distribution, in the forward cone, is a typically narrow gaussian one

  7. Penetration of a Small Caliber Projectile into Single and Multi-layered Targets

    Directory of Open Access Journals (Sweden)

    Riad A.M.

    2010-06-01

    Full Text Available The normal penetration of armor-piercing projectiles into single and multi-layered steel plates has been investigated. An experimental program has been conducted to study the effect of spaced and in-contact layered targets on their ballistic resistance. Armor piercing projectiles with caliber of 7.62 mm were fired against a series of single and multi-layered steel targets. The projectile impact velocities were ranged from 300-600 m/s, whereas the total thicknesses of the tested single, spaced and in-contact layered steel targets were 3 mm. The penetration process of different tested target configurations has been simulated using Autodayn-2D hydrocode. The experimental measurements of the present work were used to discuss the effect of impact velocity, target configurations and number of layers of different spaced and in-contact layered steel targets on their ballistic resistance. In addition, the post-firing examination of the tested targets over the used impact velocity range showed that the single and each layer of spaced and in-contact laminated steel targets were failed by petalling. Finally, the obtained experimental measurements were compared with the corresponding numerical results of Autodyn-2D hydrocode, good agreement was generally obtained.

  8. Isospin-dependent multifragmentation of relativistic projectiles

    International Nuclear Information System (INIS)

    The N/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at the GSI Schwerionen Synchrotron (SIS). Stable and radioactive Sn and La beams with an incident energy of 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. For the interpretation of the data, calculations with the statistical multifragmentation model for a properly chosen ensemble of excited sources were performed. The parameters of the ensemble, representing the variety of excited spectator nuclei expected in a participant-spectator scenario, are determined empirically by searching for an optimum reproduction of the measured fragment-charge distributions and correlations. An overall very good agreement is obtained. The possible modification of the liquid-drop parameters of the fragment description in the hot freeze-out environment is studied, and a significant reduction of the symmetry-term coefficient is found necessary to reproduce the mean neutron-to-proton ratios /Z and the isoscaling parameters of Z≤10 fragments. The calculations are, furthermore, used to address open questions regarding the modification of the surface-term coefficient at freeze-out, the N/Z dependence of the nuclear caloric curve, and the isotopic evolution of the spectator system between its formation during the initial cascade stage of the reaction and its subsequent breakup.

  9. Initiation of Detonation in Explosives by Impact of Projectiles

    OpenAIRE

    H. S. Yadav

    2006-01-01

    This paper presents a study of initiation of detonation in explosives by the impact ofprojectiles. The shock wave produced by the impact of projectiles has been considered as thestimulus for initiation of detonation. Three types of projectiles, namely (i) flyer plate, (ii) flatendedrod, and (iii) round-ended rod or a shaped charge jet, have been considered to impact andproduce a shock wave in the explosives. Deriving relations for the parameters of impact-generatedshock wave in the explosives...

  10. Theoretical design and modeling of an Infantry railgun projectile

    OpenAIRE

    Brady, James A.

    2005-01-01

    In order for railgun technology to be relevant to the Infantry, the design of the projectile must incorporate the following three concepts: an effective ballistics package, geometries for aerodynamic stability; and a non-parasitic conducting armature. I designed an effective 30mm and scaled 40mm projectile which incorporates the aforementioned concepts. My ballistics analysis concluded with two AUTODYN. finite-element computer models that refined theoretical estimates for target penetration. ...

  11. Simultaneous Projectile-Target Excitation in Heavy Ion Collisions

    OpenAIRE

    Benesh, C. J.; Friar, J. L.

    1994-01-01

    We calculate the lowest-order contribution to the cross section for simultaneous excitation of projectile and target nuclei in relativistic heavy ion collisions. This process is, to leading order, non-classical and adds incoherently to the well-studied semi-classical Weizs\\"acker-Williams cross section. While the leading contribution to the cross section is down by only $1/Z_P$ from the semiclassical process, and consequently of potential importance for understanding data from light projectil...

  12. Analysis of Penetration Model for Geo-Material by Rigid Projectile

    Institute of Scientific and Technical Information of China (English)

    LI Jianchun; MA Guowei; YU Maohong

    2006-01-01

    Based on the cylindrical cavity expansion theory,a plastic-damage-elastic model is proposed for the penetration problem of geo-material.In the model,the unified strength criterion (Yu,1991) is adopted as the failure criterion.The distributions of the radial stress and velocity are analyzed.According to the Newton's second law,a series results of the final penetration depth and the impedance load are obtained to different parameter b,when a rigid projectile normally impacts and penetrates a semi-infinite geo-material target with an impact velocity of 300-1 200 m/s.By comparing with the test data available,it appears that the method can be used in analyzing the final depth and the impedance load of a rigid projectile penetrating into a semi-infinite target with different impact velocities.

  13. Effect of CFRP strengthening on the response of RC slabs to hard projectile impact

    Energy Technology Data Exchange (ETDEWEB)

    Almusallam, Tarek; Al-Salloum, Yousef; Alsayed, Saleh; Iqbal, Rizwan; Abbas, Husain, E-mail: abbas_husain@hotmail.com

    2015-05-15

    Highlights: • Studied response of CFRP-strengthened RC slabs under the impact load. • Slabs were tested under the strike of hemispherical steel projectiles at varying impact. • The slabs were analyzed numerically using LS-DYNA. • Strengthening increased the ballistic limit velocity by 18% and perforation energy by 56.7%. • CFRP sheet reduced the crater damage and contained the flying concrete fragments. - Abstract: In this paper impact response of CFRP-strengthened RC panels under the impact of non-deformable projectiles has been presented. The control and CFRP-strengthened RC slab panels were tested under the strike of hemispherical nosed steel projectiles at varying impact velocities. The response of these panels was investigated experimentally as well as numerically. The damage of the slab panels was measured in terms of the penetration depth, formation of cracks, spalling and scabbing areas and fracture of CFRP sheet. This study presents a practical and efficient numerical method for analyzing the impact response of CFRP-strengthened RC structures using LS-DYNA. The CFRP strengthening was found to increase the ballistic limit velocity by 18%, perforation energy of RC slabs by 56.7%, reduce the front crater damage and contains the flying of concrete fragments from the rear face. The maximum impact force occurs at almost same penetration depth for the control and CFRP-strengthened slabs but the restraint provided by CFRP increased the penetration depth by about 1/19.3 of the thickness of slab.

  14. Effect of CFRP strengthening on the response of RC slabs to hard projectile impact

    International Nuclear Information System (INIS)

    Highlights: • Studied response of CFRP-strengthened RC slabs under the impact load. • Slabs were tested under the strike of hemispherical steel projectiles at varying impact. • The slabs were analyzed numerically using LS-DYNA. • Strengthening increased the ballistic limit velocity by 18% and perforation energy by 56.7%. • CFRP sheet reduced the crater damage and contained the flying concrete fragments. - Abstract: In this paper impact response of CFRP-strengthened RC panels under the impact of non-deformable projectiles has been presented. The control and CFRP-strengthened RC slab panels were tested under the strike of hemispherical nosed steel projectiles at varying impact velocities. The response of these panels was investigated experimentally as well as numerically. The damage of the slab panels was measured in terms of the penetration depth, formation of cracks, spalling and scabbing areas and fracture of CFRP sheet. This study presents a practical and efficient numerical method for analyzing the impact response of CFRP-strengthened RC structures using LS-DYNA. The CFRP strengthening was found to increase the ballistic limit velocity by 18%, perforation energy of RC slabs by 56.7%, reduce the front crater damage and contains the flying of concrete fragments from the rear face. The maximum impact force occurs at almost same penetration depth for the control and CFRP-strengthened slabs but the restraint provided by CFRP increased the penetration depth by about 1/19.3 of the thickness of slab

  15. Electronic emission produced by light projectiles at intermediate energies

    International Nuclear Information System (INIS)

    Two aspects of the electronic emission produced by light projectiles of intermediate energies have been studied experimentally. In the first place, measurements of angular distributions in the range from θ = 0 deg -50 deg induced by collisions of 50-200 keV H+ incident on He have been realized. It was found that the double differential cross section of electron emission presents a structure focussed in the forward direction and which extends up to relatively large angles. Secondly, the dependence of the double differential cross section on the projectile charge was studied using H+ and He32+ projectiles of 50 and 100 keV/amu incident on He. Strong deviations from a constant scaling factor were found for increasing projectile charge. The double differential cross sections and the single differential cross sections as a function of the emission angle, and the ratios of the emissions induced by He32+ and H+ at equal incident projectile velocities are compared with the 'Continuum Distorted Wave-Eikonal Initial State' (CDW-EIS) approximation and the 'Classical Trajectory Monte Carlo' (CTMC) method. Both approximations, in which the potential of the projectile exercises a relevant role, reproduce the general aspects of the experimental results. An electron analyzer and the corresponding projectile beam line has been designed and installed; it is characterized by a series of properties which are particularly appropriate for the study of double differential electronic emission in gaseous as well as solid targets. The design permits to assure the conditions to obtain a well localized gaseous target and avoid instrumental distortions of the measured distributions. (Author)

  16. Electromagnetic Dissociation of Target Nuclei by $^{16}$O and $^{32}$S Projectiles

    CERN Multimedia

    2002-01-01

    We have measured the inclusive cross sections for electromagnetic dissociation (ED) of |1|9|7Au targets by 60 and 200~GeV/nucleon |1|6O and 200~ GeV/nucleon |3|2S projectiles. This is an extension of similar measurements carried out earlier at 2~GeV/nucleon. ED is a purely electromagnetic process occuring when a virtual photon is exchanged between projectile and target. The experiment emphasized precise measurement of total one-neutron-out cross sections. A secondary goal was to test the applicability of the concepts of factorization and limiting fragmentation at ultrarelativistic energies.\\\\ \\\\ Each individual target will be irradiated upstream and parasitic to experiment NA38 on the dimuon spectrometer. Cross sections for reactions of interest will be determined by off-line counting of the appropriate residual @g~ray activities in Ames, Iowa, USA. Preliminary results indicate an ED one-neutron removal cross section for 200~GeV/nucleon |1|6O projectiles on |1|9|7Au of approximately 0.45~barns. The result is ...

  17. SCORPION: a system for coincidences between recoil and projectile ions at NSC, New Delhi

    International Nuclear Information System (INIS)

    An on-line facility to measure coincidences between the recoil ions and the scattered projectiles (SCORPION) has been designed, fabricated and commissioned at Nuclear Science Centre (NSC), New Delhi. The facility consists of a four jaw slit assembly, a time of flight (TOF) spectrometer, a parallel plate electrostatic charge analyser and a one dimensional position sensitive parallel plate avalanche counter (PPAC). Details of the design and working principles of various components and the test results obtained for the Siq+ -Ar collision system are presented to highlight the performance of the system. A multiple loss of up to four electrons has been observed for 60 MeV Si4+ ions colliding with argon atoms in a single collision condition. Spectra of recoil ions detected in coincidence with a particular charge state of the scattered projectile show a bell shaped distribution as a function of the recoil charge state (r) for the electron loss events. However, the yield of recoil ions drops as r increases for the direct ionization channel. Also for electron loss, the peak of the recoil ion distribution is seen to shift to a higher recoil charge state as the number of lost electrons from the projectile increases. (author)

  18. Influence of projectile neutron number on cross section in cold fusion reactions

    International Nuclear Information System (INIS)

    Elements 107-112 [1,2] have been discovered in reactions between 208Pb or 209Bi targets and projectiles ranging from 54Cr through 70Zn. In such reactions, the compound nucleus can be formed at excitation energies as low as ∼12 MeV, thus this type of reaction has been referred to as 'cold fusion'. The study of cold fusion reactions is an indispensable approach to gaining a better understanding of heavy element formation and decay. A theoretical model that successfully predicts not only the magnitudes of cold fusion cross sections, but also the shapes of excitation functions and the cross section ratios between various reaction pairs was recently developed by Swiatecki, Siwek-Wilczynska, and Wilczynski [3,4]. This theoretical model, also referred to as Fusion by Diffusion, has been the guide in all of our cold fusion studies. One particularly interesting aspect of this model is the large predicted difference in cross sections between projectiles differing by two neutrons. The projectile pair where this difference is predicted to be largest is 48Ti and 50Ti. To test and extend this model, 208Pb(48Ti,n)255Rf and 208Pb(50Ti,n)257Rf excitation functions were recently measured at the Lawrence Berkeley National Laboratory's (LBNL) 88-Inch Cyclotron utilizing the Berkeley Gas-filled Separator (BGS). The 50Ti reaction was carried out with thin lead targets (∼100 (micro)g/cm2), and the 48Ti reaction with both thin and thick targets (∼470 (micro)g/cm2). In addition to this reaction pair, reactions with projectile pairs 52Cr and 54Cr [5], 56Fe and 58Fe [6], and 62Ni [7] and 64Ni [8] will be discussed and compared to the Fusion by Diffusion predictions. The model predictions show a very good agreement with the data

  19. A Mass Loss Penetration Model to Investigate the Dynamic Response of a Projectile Penetrating Concrete considering Mass Abrasion

    Directory of Open Access Journals (Sweden)

    NianSong Zhang

    2015-01-01

    Full Text Available A study on the dynamic response of a projectile penetrating concrete is conducted. The evolutional process of projectile mass loss and the effect of mass loss on penetration resistance are investigated using theoretical methods. A projectile penetration model considering projectile mass loss is established in three stages, namely, cratering phase, mass loss penetration phase, and remainder rigid projectile penetration phase.

  20. Design limitations for small caliber electromagnetic saboted rod projectiles

    International Nuclear Information System (INIS)

    In any application of electromagnetic launch, the armature package must conform to the barrel and provide the desired terminal performance. Finned long rod projectiles have proven to be viable candidates for both flight bodies and terminal effectiveness. This paper describes the criteria necessary for integrating a solid armature with a conventional type finned rod. An initial design is presented for a rod projectile, launched from a 15.24 mm (.60 caliber) augmented railgun with a sinusoidal driving current. Other designs are assessed in order to explore improvements and scalability to other bore diameters. The authors evaluate the final armature design considering: launch, flight, and terminal effects. ohmic heating, structural limitations, and barrel parameters are also discussed. Flight and aerodynamic data are scaled from existing finned rod projectile data bases to calculate horizontal flat-trajectory performance. Finally, terminal effects are incorporated for a simple rolled homogeneous armor (RHA) target

  1. Fragmentation of Pb-Projectiles at SPS Energies

    CERN Multimedia

    2002-01-01

    % EMU17 \\\\ \\\\ We have exposed stacks consisting of solid state nuclear track detectors (CR-39 plastic and BP-1 glass) and different target materials at the SPS to beams of Pb projectiles. Our detectors record tracks of relativistic nuclei with charge numbers of Z~$\\geq$~6 for CR-39 and Z~$\\geq$75 for BP-1. After development of the tracks by etching they are detected and measured using completely automated microscope systems. Thus experiments with high statistics are possible. \\\\ \\\\BP-1 detectors were exposed to measure total charge changing cross sections and elemental production cross sections for heavy projectile fragments. These experiments were performed for different targets CH$ _{2} $, C, Al, Cu, Ag and Pb. Comparison of the results for different targets allows to investigate contributions to charge changing reactions by electromagnetic dissociation. Multifragmentation events in which several intermediate mass fragments are emitted from the heavy Pb projectile are studied using stacks containing CR-39 d...

  2. Optical potentials for p-shell heavy ion projectiles

    International Nuclear Information System (INIS)

    Elastic and inelastic scatterings of 12C, 13C, 14N, and 16O projectiles on 28Si have been studied at corresponding bombarding energies to the scattering in regions of the vicinity of the strong absorption radius. Optical model and microscopic double-folding model analyses have been performed in order to define the nature of the optical potential depending on the projectiles. The analysis by the optical model calculations showed that the shallow potential (V/sub R/ = 10 MeV) was not adequate for reproducing both the measured elastic and inelastic angular distributions, and a spin-dependent noncentral potential for the scattering systems 13C,14N+28Si was indispensable for obtaining the similar central potentials for all four projectiles. Analysis by the microscopic double-folding calculations supported the results of the optical model calculations

  3. Projectile transverse motion and stability in electromagnetic induction launchers

    Energy Technology Data Exchange (ETDEWEB)

    Shokair, I.R.

    1993-12-31

    The transverse motion of a projectile in an electromagnetic induction launcher is considered. The equations of motion for translation and rotation are derived assuming a rigid projectile and a flyway restoring force per unit length that is proportional to the local displacement. Linearized transverse forces and torques due to energized coils are derived for displaced or tilted armature elements based on a first order perturbation method. The resulting equations of motion for a rigid projectile composed of multiple elements in a multi-coil launcher are analyzed as a coupled oscillator system of equations and a simple linear stability condition is derived. The equations of motion are incorporated into the 2-D Slingshot circuit code and numerical solutions for the transverse motion are obtained. For a launcher with a 10 cm bore radius with a 40 cm long solid armature, we find that stability is achieved with a restoring force (per unit length) constant of k {approx} 1 {times} 10{sup 8} N/m{sup 2}. For k = 1.5 {times} 10{sup 8} N/m{sup 2} and sample coil misalignment modeled as a sine wave of 1 mm amplitude at wavelengths of one or two meters, the projectile displacement grows to a maximum of 4 mm. This growth is due to resonance between the natural frequency of the projectile transverse motion and the coil displacement wavelength. This resonance does not persist because of the changing axial velocity. Random coil displacement is also found to cause roughly the same projectile displacement. For the maximum displacement a rough estimate of the transverse pressure is 50 bars. Results for a wound armature with uniform current density throughout show very similar displacements.

  4. Disappearance of isospin effect in projectile fragmentation at intermediate energy

    International Nuclear Information System (INIS)

    The 140 MeV/u 40,48Ca+9Be and 58,64Ni+9Be reactions are simulated by the statistical abrasion ablation model, and the simulation results are compared to the National Superconducting Cyclotron Laboratory (NSCL) experimental data. By comparing the fragment isotopic distributions of 40,48Ca and 58,64Ni, we study the isospin effect in the projectile fragmentation induced by the neutron-rich nuclei at intermediate energy experimentally and theoretically. It is found that the isospin effect in projectile fragmentation decreases and even disappears as the violence of the collision increases. (nuclear physics)

  5. PERFORATION OF PLASTIC SPHERICAL SHELLS UNDER IMPACT BY CYLINDRICAL PROJECTILES

    Institute of Scientific and Technical Information of China (English)

    NING Jian-guo; SONG Wei-dong

    2006-01-01

    The objective is to study the perforation of a plastic spherical shell impacted by a cylindrical projectile. First, the deformation modes of the shell were given by introducing an isometric transformation. Then, the perforation mechanism of the shell was analyzed and an analytical model was advanced. Based on Hamilton principle, the governing equation was obtained and solved using Runge-Kuta method. Finally, some important theoretical predictions were given to describe the perforation mechanism of the shell. The results will play an important role in understanding the perforation mechanism of spherical shells impacted by a projectile.

  6. Dimensional Analysis on the Perforation of Stiffened Plates by Projectiles

    Institute of Scientific and Technical Information of China (English)

    SONG Wei-dong; NING Jian-guo

    2007-01-01

    The phenomena attendant to the perforation of truncated oval shape projectile in to multi-layered stiffened plates were investigated. Dimensional analysis was employed to give an empirical formula. Then a membership function was introduced to modify the empirical formula. The effects of initial velocities, base plate thicknesses, height and width of stiffener on residual velocities were explored. The predictions of the empirical formula are in reasonably good agreement with those of experiment and numerical results. All these results indicate that the empirical formula is capable of predicting the residual velocity of the projectile penetrating the multi-layered stiffened plates.

  7. Testing the Accuracy of a Projectile Motion Apparatus

    Science.gov (United States)

    Henderson, Bret; Martell, Eric

    2013-03-01

    The purpose of this research is to predict where a ball would land given initial velocity, angular velocity, and atmospheric conditions. A spinning spherical object flying through air is affected by gravity, quadratic drag forces, and the Magnus force. Mathematica was used to numerically solve predictions for the equations of motion. These predictions were compared with experimental data gathered by launching tennis balls, baseballs, and/or soccer balls from a machine we designed to propel the balls with a pre-determined initial velocity and initial angular velocity.

  8. Simulations of the Penetration of 6061-T6511 Aluminum Targets by Spherical-Nosed VAR 4340 Steel Projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Tabbara, M.R.; Warren, T.L.

    1998-10-21

    In certain penetration events it is proposed that the primary mode of deformation of the target can be approximated by known analytical expressions. In the context of an analysis code, this approximation eliminates the need for discretizing the target as well as the need for a contact algorithm. Thus, this method substantially reduces the computer time and memory requirements. In this paper a forcing function which is derived from a spherical-cavity expansion (SCE) analysis has been implemented in a transient dynamic finite element code. This irnplementation is capable of computing the structural and component responses of a projectile due to a three dimensional penetration event. Simulations are presented for 7.1 l-mm-diameter, 74.7-mm-long, spherical-nose, vacuum- arc-remelted (VAR) 4340 steel projectiles that penetrate 6061-T6511 aluminum targets. Final projectile configurations obtained from the simulations are compared with post-test radiographs obtained from the corresponding experiments. It is shown that the simulations accurately predict the permanent projectile deformation for three dimensional loadings due to incident pitch and yaw over a wide range of striking velocities.

  9. MEMIN: Chemical Modification of Projectile Spheres, Target Melts and Shocked Quartz in Hypervelocity Impact Experiments

    Science.gov (United States)

    Ebert, M.; Hecht, L.; Deutsch, A.; Kenkmann, T.

    2011-03-01

    We present results of hypervelocity cratering experiments using iron meteorite as projectile and a sandstone target. The ejecta show shock features (melting, PDFs, lechatelierite) and physical as well as chemical mixing between projectile and target.

  10. 3D Numerical Simulation of Projectile Penetration into Concrete Target

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Basing on the explicit instantaneous dynamics software MSC-Dytran and the general coupling arithmetic, the process of the projectile penetration into concrete target was simulated with the point-line-surface-body modeling method. Simulation results are in agreement with experimental results. The simulated data could provide design reference for the defense engineering construction and penetrator design.

  11. Projectile deformation effects in the breakup of $^{37}$Mg

    CERN Document Server

    Shubhchintak,; Shyam, R

    2015-01-01

    We study the breakup of $^{37}$Mg on Pb at 244MeV/u with the recently developed extended theory of Coulomb breakup within the post-form finite range distorted wave Born approximation that includes deformation of the projectile. Comparing our calculated cross section with the available Coulomb breakup data we determine the possible ground state configuration of $^{37}$Mg.

  12. Using Tracker as a Pedagogical Tool for Understanding Projectile Motion

    Science.gov (United States)

    Wee, Loo Kang; Chew, Charles; Goh, Giam Hwee; Tan, Samuel; Lee, Tat Leong

    2012-01-01

    This article reports on the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When a computer model building learning process is supported and driven by video analysis data, this free Open Source Physics tool can provide opportunities for students to engage in active enquiry-based…

  13. Behaviour of a Kinetic Energy Projectile on Angular Impact

    Directory of Open Access Journals (Sweden)

    R. A. Goel

    1988-07-01

    Full Text Available Experiments of high velocity impact have been carried out with 30 mm armoured piercing projectiles on 55 mm thick hard steel plate. Angle of impact has been varied from 10" to 90". Damage inflicted on target with varying angle of impact has been reported and discussed in this paper. Comparative behaviour with 20 mm APP shot has also been discussed.

  14. On the Trajectories of Projectiles Depicted in Early Ballistic Woodcuts

    Science.gov (United States)

    Stewart, Sean M.

    2012-01-01

    Motivated by quaint woodcut depictions often found in many late 16th and 17th century ballistic manuals of cannonballs fired in air, a comparison of their shapes with those calculated for the classic case of a projectile moving in a linear resisting medium is made. In considering the asymmetrical nature of such trajectories, the initial launch…

  15. Ionization of hydrogen by a relativistic heavy projectile

    International Nuclear Information System (INIS)

    Using a relativistic analogue of the classical trajectory Monte-Carlo method we investigate the influence of the magnetic field of a relativistic heavy projectile on the ionization cross section of hydrogen. In particular we focus our attention on the angular and energy distribution of the emitted delta electrons. (orig.)

  16. Calculation of forces arising from impacting projectiles upon yielding structures

    International Nuclear Information System (INIS)

    Calculations concerning the impact of airplanes upon nuclear power plant buildings usually imply that the building [QUOTE]acts' as a rigid target. This assumption is justified for considerations concerning the structural integrity of the building being hit. However, for investigating induced vibrations of components within the structure, this approach might-in general-be too conservative. It is expected, that yielding of the structure during impact reduces the peak values of the loads and changes the temporal behaviour of the load function which is obtained for a rigid target. To calculate the changes of the load function which are due to deformations of the structure, Riera's method is extended for the case of a yielding target. The calculations are performed with a one-dimensional model for the projectile. The presented model calculations seem to verify that the motion of the target does not have much influence on the impact force for projectiles similar to the model projectile, provided the displacement of the yielding target is small in comparison with the path covered by the free-flying projectile during a time which is equivalent to the total time of impact. (Auth.)

  17. Wound Ballistics Modeling for Blast Loading Blunt Force Impact and Projectile Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Paul A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cooper, Candice Frances [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Burnett, Damon J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Light body armor development for the warfighter is based on trial-and-error testing of prototype designs against ballistic projectiles. Torso armor testing against blast is virtually nonexistent but necessary to ensure adequate protection against injury to the heart and lungs. In this report, we discuss the development of a high-fidelity human torso model, it's merging with the existing Sandia Human Head-Neck Model, and development of the modeling & simulation (M&S) capabilities necessary to simulate wound injury scenarios. Using the new Sandia Human Torso Model, we demonstrate the advantage of virtual simulation in the investigation of wound injury as it relates to the warfighter experience. We present the results of virtual simulations of blast loading and ballistic projectile impact to the tors o with and without notional protective armor. In this manner, we demonstrate the ad vantages of applying a modeling and simulation approach to the investigation of wound injury and relative merit assessments of protective body armor without the need for trial-and-error testing.

  18. Performance of primary repair on colon injuries sustained from low-versus high-energy projectiles.

    Science.gov (United States)

    Lazovic, Ranko; Radojevic, Nemanja; Curovic, Ivana

    2016-04-01

    Among various reasons, colon injuries may be caused by low- or high-energy firearm bullets, with the latter producing a temporary cavitation phenomenon. The available treatment options include primary repair and two-stage management, but recent studies have shown that primary repair can be widely used with a high success rate. This paper investigates the differences in performance of primary repair on these two types of colon injuries. Two groups of patients who sustained colon injuries due to single gunshot wounds, were retrospectively categorized based on the type of bullet. Primary colon repair was performed in all patients selected based on the inclusion and exclusion criteria (Stone and Fabian's criteria). An almost absolute homogeneity was attained among the groups in terms of age, latent time before surgery, and four trauma indexes. Only one patient from the low-energy firearm projectile group (4%) developed a postsurgical complication versus nine patients (25.8%) from the high-energy group, showing statistically significant difference (p = 0.03). These nine patients experienced the following postsurgical complications: pneumonia, abscess, fistula, suture leakage, and one multiorgan failure with sepsis. Previous studies concluded that one-stage primary repair is the best treatment option for colon injuries. However, terminal ballistics testing determined the projectile's path through the body and revealed that low-energy projectiles caused considerably lesser damage than their high-energy counterparts. Primary colon repair must be performed definitely for low-energy short firearm injuries but very carefully for high-energy injuries. Given these findings, we suggest that the treatment option should be determined based not only on the bullet type alone but also on other clinical findings. PMID:26874437

  19. Experimental Research on Behavior of Composite Material Projectile Penetrating Concrete Target

    Institute of Scientific and Technical Information of China (English)

    ZHONG Weizhou; SONG Shuncheng; ZHANG Fangju; ZHANG Qingping; HUANG Xicheng; LI Sizhong; LU Yonggang

    2008-01-01

    Projectile made of carbon fiber composite material shell and metal warhead penetrates concrete target at speeds of 336 m/s, 447 m/s and 517 m/s.The angles between the perpendicular of target surface and projectile axis are 0° and 30° .The thickness of concrete target is 200 mm and the compression strength is 30 MPa.The experimental results indicate that the strength of composite material structure is high.Composite projectile can go through concrete target without fiber segregation and breakage.The percent fill is 18.5% in the composite material projectile.It is about twice as that of metal projectile, if the density of metal is taken as 7.8 g/cm3.Comparing with metal projectile, low-density, high-strength composite material can lessen projectile weight, improve charge-weight ratio of detonator and enhance destructive powder.

  20. Radiation hardness investigation of avalanche photodiodes for the Projectile Spectator Detector readout at the Compressed Baryonic Matter experiment

    Czech Academy of Sciences Publication Activity Database

    Kushpil, Vasilij; Mikhaylov, Vasily; Kushpil, Svetlana; Tlustý, Pavel; Svoboda, Ondřej; Kugler, Andrej

    2015-01-01

    Roč. 787, JUL (2015), s. 117-120. ISSN 0168-9002 R&D Projects: GA MŠk LG12007; GA MŠk LG14004; GA MŠk(CZ) LM2011019 Institutional support: RVO:61389005 Keywords : avalanche photodiodes * single protons detection * radiation hardness * neutron irradiation tests * compressed Baryonic Matter experiment * Projectile Spectator Detector Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.216, year: 2014

  1. Ballistics considerations for small-caliber, low-density projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Gouge, M.J.; Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Milora, S.L.; Qualls, A.L.

    1993-11-01

    One major application for single- and two-stage light gas guns is for fueling magnetic fusion confinement devices. Powder guns are not a feasible alternative due to possible plasma contamination by residual powder gases and the eventual requirement of steady-state operation at {approximately} 1 Hz, which will dictate a closed gas handling system where propellant gases are recovered, processed and recompressed. Interior ballistic calculations for single-stage light gas guns, both analytical and numerical, are compared to an extensive data base for low density hydrogenic projectiles (pellets). Some innovative range diagnostics are described for determining the size and velocity of these small (several mm) size projectiles. A conceptual design of a closed cycle propellant gas system is presented including tradeoffs between different light propellant gases.

  2. Plasma as a high-charge-state projectile stripping medium

    International Nuclear Information System (INIS)

    The classical trajectory Monte Carlo model has been used to computationally study the charge-state distributions that result from interactions between a high-energy, multielectron projectile and neutral and fully ionized targets. These studies are designed to determine the properties of a plasma for producing highly stripped ions as a possible alternative to gas and foil strippers that are commonly used to enhance the charge states of energetic ion beams. The results of these studies clearly show that a low-atomic-number, highly ionized plasma can yield higher charge states than a neutral target of the same density. The effect is principally attributable to the reduction in the number of available electron-capture channels. In this article, we compare the charge-state distributions that result during passage of a 20-MeV Pb projectile through neutral gas and fully ionized (singly charged) plasma strippers and estimate the effects of multiple scattering on the quality of the beam

  3. Performance of the Projectile Fragmentation Wall at CELSIUS Storage Ring

    Science.gov (United States)

    Siwek, A.; Budzanowski, A.; Czech, B.; Gburek, T.; Jakobsson, B.; Kozik, E.; Skwirczyńska, I.; Westerberg, L.

    The projectile fragmentation wall [Budzanowski, A. et al., Nucl. Instr. Meth. A482, 528 (2002).] (PFW) is a part of a bigger detection system comprising of the CHICSi detector [Jakobsson, B., Nucl. Phys. News Int. 9:2, 22 (1999). Siwek, A., Nucl. Phys., A654, 2695 (1999)] and a recoil detectors array [Kuznetsov, A. V. et al, Nucl. Instr. Meth. A452, 525 (2000)]. The system is designed to register products of proton- and heavy ion-induced reactions at the energies 50-450 MeV/nucleon (see Bo Jakobsson's contribution to this conference). The aim of PFW is to register and identify projectile like fragments emitted in forward direction not covered by the CHICSi detector.

  4. Projectile dependency of radioactivities of spallation products induced in copper

    International Nuclear Information System (INIS)

    The reaction cross sections of spallation products in a Cu target by 230 MeV/u C and Ne ions were obtained. Irradiation experiments were performed at HIMAC (Heavy Ion Medical Accelerator in Chiba), National Institute of Radiological Sciences. Gamma-ray spectra from activation samples were measured with a HPGe detector. From the gamma-ray spectra, we obtained the variation of reaction cross sections of Cl-38, Cr-49, Mn-55, Cu-60, Cu-61 and Co-62m in Cu sample with Cu target thickness, and compared it with the experimental data by Kim et al.. The results showed that the dependence of the cross sections to the projectile mass is very small for the same projectile energy per nucleon. (author)

  5. Mechanisms of Li-projectile breakup-up

    International Nuclear Information System (INIS)

    Various experimental and theoretical features observed in recent studies of break-up of 6Li and 7Li projectiles in the field of atomic nuclei are discussed, in particular for the transitional energy regime of 10-30 MeV/amu. The discussion is organized as three independent lectures presented at the International School on Nuclear Physics, Kiev (UkSSR), 28 May - 8 June, 1990. After a survey on the main experimental facts and on the basic reaction mechanisms, current theoretical approaches are illustrated by an application to the analysis of elastic break-up of 156 MeV 6Li projectiles. Finally Coulomb break-up is discussed as a novel tool of laboratory nuclear astrophysics. (orig.)

  6. Projectile and Lab Frame Differential Cross Sections for Electromagnetic Dissociation

    Science.gov (United States)

    Norbury, John W.; Adamczyk, Anne; Dick, Frank

    2008-01-01

    Differential cross sections for electromagnetic dissociation in nuclear collisions are calculated for the first time. In order to be useful for three - dimensional transport codes, these cross sections have been calculated in both the projectile and lab frames. The formulas for these cross sections are such that they can be immediately used in space radiation transport codes. Only a limited amount of data exists, but the comparison between theory and experiment is good.

  7. Magnus Force of Common Projectile Bodies with Turbulent Layers

    Institute of Scientific and Technical Information of China (English)

    CHEN Jun

    2005-01-01

    Calculating formulae of Magnus force on common projectile bodies (cone-shaped and parabola-shaped) with turbulent layers were built based on Magnus theory. The effects of temperature exponential were considered, and curve-fitting approaches were adopted in the research that could give more exact result data. Both flow layer constants and shape constants are presented in Magnus force formulae, which are useful to evaluate Magnus force in different states.

  8. Numerical simulation of multiphase cavitating flows around an underwater projectile

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The present simulation investigates the multiphase cavitating flow around an underwater projectile.Based on the Homogeneous Equilibrium Flow assumption,a mixture model is applied to simulate the multiphase cavitating flow including ventilated cavitation caused by air injection as well as natural cavitation that forms in a region where the pressure of liquid falls below its vapor pressure. The transport equation cavitating model is applied.The calculations are executed based on a suite of CFD code.The hyd...

  9. Projectile - Mass asymmetry systematics for low energy incomplete fusion

    Directory of Open Access Journals (Sweden)

    Singh Pushpendra P.

    2015-01-01

    Full Text Available In the present work, low energy incomplete fusion (ICF in which only a part of projectile fuses with target nucleus has been investigated in terms of various entrance channel parameters. The ICF strength function has been extracted from the analysis of experimental excitation functions (EFs measured for different projectile-target combinations from near- to well above- barrier energies in 12C,16O(from 1.02Vb to 1.64Vb+169Tm systems. Experimental EFs have been analysed in the framework statistical model code PACE4 based on the idea of equilibrated compound nucleus decay. It has been found that the value of ICF fraction (FICF increases with incident projectile energy. A substantial fraction of ICF (FICF ≈ 7 % has been accounted even at energy as low as ≈ 7.5% above the barrier (at relative velocity νrel ≈0.027 in 12C+169Tm system, and FICF ≈ 10 % at νrel ≈0.014 in 16O+169Tm system. The probability of ICF is discussed in light of the Morgenstern’s mass-asymmetry systematics. The value of FICF for 16O+169Tm systems is found to be 18.3 % higher than that observed for 12C+169Tm systems. Present results together with the re-analysis of existing data for nearby systems conclusively demonstrate strong competition of ICF with CF even at slightly above barrier energies, and strong projectile dependence that seems to supplement the Morgenstern’s systematics.

  10. Schottky Mass Spectrometry on 152Sm Projectile Fragments*

    Science.gov (United States)

    Yan, X. L.; Litvinov, Yu. A.; Bosch, F.; Brandau, C.; Chen, L.; Geissel, H.; Knöbel, R.; Kozhuharov, C.; Kurcewicz, J.; Litvinov, S. A.; Münzenberg, G.; Nociforo, C.; Nolden, F.; Plass, W. R.; Sanjari, M. S.; Scheidenberger, C.; Steck, M.; Sun, B.; Tu, X. L.; Wang, M.; Weick, H.; Winckler, N.; Winkler, M.; Xu, H. S.; Zhang, Y. H.; Zhou, X. H.

    Direct mass measurements of neutron-deficient 152Sm projectile fragments were conducted at the FRS-ESR facility at GSI by employing the time-resolved Schottky Mass Spectrometry. 311 different nuclides were identified by means of their revolution frequencies. Charge-dependent systematic differences between the fitted mass values and the literature mass values are observed in the data analysis. The origin of this systematic deviation is still under discussion. The latest progress on the data analysis is presented.

  11. Learning Projectile Motion with the Computer Game ``Scorched 3D``

    Science.gov (United States)

    Jurcevic, John S.

    2008-01-01

    For most of our students, video games are a normal part of their lives. We should take advantage of this medium to teach physics in a manner that is engrossing for our students. In particular, modern video games incorporate accurate physics in their game engines, and they allow us to visualize the physics through flashy and captivating graphics. I recently used the game "Scorched 3D" to help my students understand projectile motion.

  12. Influence of projectile neutron number on cross section in cold fusion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Dragojevic, Irena; Dragojevic, I.; Gregorich, K.E.; Dullmann, Ch.E.; Folden III, C.M.; Garcia, M.A.; Gates, J.M.; Nelson, S.L.; Sudowe, R.; Nitsche, H.

    2007-09-01

    Elements 107-112 [1,2] have been discovered in reactions between {sup 208}Pb or {sup 209}Bi targets and projectiles ranging from {sup 54}Cr through {sup 70}Zn. In such reactions, the compound nucleus can be formed at excitation energies as low as {approx}12 MeV, thus this type of reaction has been referred to as 'cold fusion'. The study of cold fusion reactions is an indispensable approach to gaining a better understanding of heavy element formation and decay. A theoretical model that successfully predicts not only the magnitudes of cold fusion cross sections, but also the shapes of excitation functions and the cross section ratios between various reaction pairs was recently developed by Swiatecki, Siwek-Wilczynska, and Wilczynski [3,4]. This theoretical model, also referred to as Fusion by Diffusion, has been the guide in all of our cold fusion studies. One particularly interesting aspect of this model is the large predicted difference in cross sections between projectiles differing by two neutrons. The projectile pair where this difference is predicted to be largest is {sup 48}Ti and {sup 50}Ti. To test and extend this model, {sup 208}Pb({sup 48}Ti,n){sup 255}Rf and {sup 208}Pb({sup 50}Ti,n){sup 257}Rf excitation functions were recently measured at the Lawrence Berkeley National Laboratory's (LBNL) 88-Inch Cyclotron utilizing the Berkeley Gas-filled Separator (BGS). The {sup 50}Ti reaction was carried out with thin lead targets ({approx}100 {micro}g/cm{sup 2}), and the {sup 48}Ti reaction with both thin and thick targets ({approx}470 {micro}g/cm{sup 2}). In addition to this reaction pair, reactions with projectile pairs {sup 52}Cr and {sup 54}Cr [5], {sup 56}Fe and {sup 58}Fe [6], and {sup 62}Ni [7] and {sup 64}Ni [8] will be discussed and compared to the Fusion by Diffusion predictions. The model predictions show a very good agreement with the data.

  13. Projectile energy loss in multiply ionizing ion-atom collisions

    International Nuclear Information System (INIS)

    The projectile energy loss for 7.5--25-MeV C6+,5+ and F6+ ions was measured for single collisions with He, Ne, Ar, and Kr as a function of the recoil-ion charge state and the projectile scattering. This energy loss was measured for collisions in which the projectile captured an electron and for those involving just direct ionization. We investigated and found a large average energy transfer (100--250 eV/electron) to the continuum electrons. A strong increase of the scattering angle with recoil-ion charge state was observed for both capture and direct ionization. The results imply that, for smaller impact parameters, higher recoil-ion charge states are produced and that higher energy losses are obtained. We observed a weak target-Z dependence of the energy loss. The results are compared with n-body classical-trajectory Monte Carlo calculations by Olson, semiclassical-approximation calculations by Schuch et al. [Nucl. Instrum. Methods Phys. Res. Sect. B 42, 566 (1989)], and the energy-deposition model

  14. Chunk projectile launch using the Sandia Hypervelocity Launcher Facility

    Energy Technology Data Exchange (ETDEWEB)

    Chhabildas, L.C.; Trucano, T.G.; Reinhart, W.D.; Hall, C.A.

    1994-07-01

    An experimental technique is described to launch an intact ``chunk,`` i.e. a 0.3 cm thick by 0.6 cm diameter cylindrical titanium alloy (Ti-6Al-4V) flyer, to 10.2 km/s. The ability to launch fragments having such an aspect ratio is important for hypervelocity impact phenomenology studies. The experimental techniques used to accomplish this launch were similar but not identical to techniques developed for the Sandia HyperVelocity Launcher (HVL). A confined barrel impact is crucial in preventing the two-dimensional effects from dominating the loading response of the projectile chunk. The length to diameter ratio of the metallic chunk that is launched to 10.2 km/s is 0.5 and is an order of magnitude larger than those accomplished using the conventional hypervelocity launcher. The multi-dimensional, finite-difference (finite-volume), hydrodynamic code CTH was used to evaluate and assess the acceleration characteristics i.e., the in-bore ballistics of the chunky projectile launch. A critical analysis of the CTH calculational results led to the final design and the experimental conditions that were used in this study. However, the predicted velocity of the projectile chunk based on CTH calculations was {approximately} 6% lower than the measured velocity of {approximately}10.2 km/S.

  15. Initiation of Detonation in Explosives by Impact of Projectiles

    Directory of Open Access Journals (Sweden)

    H.S. Yadav

    2006-04-01

    Full Text Available This paper presents a study of initiation of detonation in explosives by the impact ofprojectiles. The shock wave produced by the impact of projectiles has been considered as thestimulus for initiation of detonation. Three types of projectiles, namely (i flyer plate, (ii flatendedrod, and (iii round-ended rod or a shaped charge jet, have been considered to impact andproduce a shock wave in the explosives. Deriving relations for the parameters of impact-generatedshock wave in the explosives and projectiles, and the sound velocity in the compressed explosives,it has been shown that the difference of kinetic energy of the flyer plate before and after theimpact, which is equal to the total energy of the shock wave in the explosives, leads to criticalenergy criterion for shock initiation of explosives. In this study, the critical criterion has beenused to derive the relations for initiation of explosives by a shaped charge jet, Vj2 D = K0 , whereV j and D denote the velocity and diameter of the jet, and K0 is a constant of the explosive.

  16. Theoretical Design and Computational Fluid Dynamic Analysis of Projectile Intake

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2011-08-01

    Full Text Available With the development of the science and technology, the more requirements such as cost effective, high specific impulse in wide operation rang, becomes stricter and multiplicity. However, the existing supersonic inlet can no longer adjust to all the new projectiles. In this paper, based on the basic characteristic of inlet and considering the design requirements, the two-dimensional supersonic projectile inlet was designed and verified by numerical simulation under different operating conditions such as attack angle, altitude, and so on. The results are shown that: 1 The design process is successful, but the working conditions should be limited to the small angle of attack; 2 The total pressure recovery coefficient is increasing as the Ma number increases, and then is gradually decreased after the point of Mach number is equal to 0.5; 3 The existence of attack angle reduces values of total pressure recovery. And moreover, the shock wave which occurs at the anterior point is gradually deviating from projectile body direction with the increase of attack angle; 4. The variance ratio in the outlet has the acute changed with increasing of altitudes clearly, but its corresponding values degrade sharply in the entrance.

  17. Yields of Projectile Fragments in Sulphur-Emulsion Interactions at 3.7 GeV/nucleon

    CERN Document Server

    Kamel, S; Fayed, M

    2016-01-01

    This work presents the basic characteristics of singly, doubly and heavily charged projectile fragments emitted in inelastic interactions of 32S ions with photo-emulsion nuclei at Dubna energy (3.7 GeV/nucleon). The relationship between the projectile mass and the charge of the projectile fragments is investigated, reflecting the importance of the projectile size. The mean multiplicities of different charged projectile fragments are studied and are found to increase linearly with the projectile mass. The yields of projectile fragments broke up from the interactions of 32S projectile nuclei with the different target nuclei in a nuclear emulsion are studied and they indicate that the projectile breakup mechanism seems to be independent of the target mass. A study of the multiplicity distributions of singly and doubly charged projectile fragments seem to be energy independent.

  18. Fragmentation of a 500 MeV/nucleon 86Kr beam, investigated at the GSI projectile fragment separator

    International Nuclear Information System (INIS)

    Production cross-sections and longitudinal momentum distributions have been investigated for reactions between a 500 MeV/nucleon 86Kr beam and beryllium, copper and tantalum targets. Fragments in a wide A/Z range were studied at the projectile-fragment separator FRS at GSI. The experimental production cross-sections have been used for testing the predictions obtained from a semi-empirical parameterization, a statistical abrasion model and an intranuclear-cascade model. The present study allows to extrapolate the production cross-sections towards very neutron-rich isotopes such as the doubly magic nucleus 78Ni. For fragments close to the projectile the measured longitudinal momentum distributions agrees qualitatively with a semi-empirical parameterization, which is based on the two-step picture of the fragmentation process. The momentum widths of lighter fragments, however, show deviations from this simple picture. (orig.)

  19. Assessment of two fast codes used for preliminary aerodynamic design of guided projectiles

    Science.gov (United States)

    Mikhail, Ameer G.

    1986-07-01

    Two missile aerodynamic prediction fast codes, namely NSWCAP and Missile-DATCOM, have been applied to the geometry of the guided, gun-launched Copperhead projectile. Assessment of the two codes was made in comparison with wind tunnel and free-flight range test data. Two configurations were considered for computation: the launch configuration (body-tail) in the Mach range of 0.5 to 1.8 and the maneuvering configuration (body-wing-tail) in the Mach range of 0.3 to 0.95. Results show reasonable agreement for the drag coefficient, C sub D, and show very large disagreements for both C sub N sub alpha and C sub M sub alpha. The incapability of both codes to include body slots and fin gap effects seems to have contributed largely to these differences. The dynamic derivatives C sub l sub p and (C sub M sub q + C sub M sub alpha) are not adequately estimated by the NSWCAP code, and are not calculated in the DATCOM code. For the coefficients actually computed, the DATCOM code results were slightly more accurate than those of the NSWCAP code. Both codes lack the determination of the explicit effects of control surface deflection angles on the aerodynamic coefficients. Development is needed for the determination if both codes are to be used for predictions for guided projectiles. Several areas of improvements in both codes are identified.

  20. Survivability of copper projectiles during hypervelocity impacts in porous ice: A laboratory investigation of the survivability of projectiles impacting comets or other bodies

    Science.gov (United States)

    McDermott, K. H.; Price, M. C.; Cole, M.; Burchell, M. J.

    2016-04-01

    During hypervelocity impact (>a few km s-1) the resulting cratering and/or disruption of the target body often outweighs interest on the outcome of the projectile material, with the majority of projectiles assumed to be vaporised. However, on Earth, fragments, often metallic, have been recovered from impact sites, meaning that metallic projectile fragments may survive a hypervelocity impact and still exist within the wall, floor and/or ejecta of the impact crater post-impact. The discovery of the remnant impactor composition within the craters of asteroids, planets and comets could provide further information regarding the impact history of a body. Accordingly, we study in the laboratory the survivability of 1 and 2 mm diameter copper projectiles fired onto ice at speeds between 1.00 and 7.05 km s-1. The projectile was recovered intact at speeds up to 1.50 km s-1, with no ductile deformation, but some surface pitting was observed. At 2.39 km s-1, the projectile showed increasing ductile deformation and broke into two parts. Above velocities of 2.60 km s-1 increasing numbers of projectile fragments were identified post impact, with the mean size of the fragments decreasing with increasing impact velocity. The decrease in size also corresponds with an increase in the number of projectile fragments recovered, as with increasing shock pressure the projectile material is more intensely disrupted, producing smaller and more numerous fragments. The damage to the projectile is divided into four classes with increasing speed and shock pressure: (1) minimal damage, (2) ductile deformation, start of break up, (3) increasing fragmentation, and (4) complete fragmentation. The implications of such behaviour is considered for specific examples of impacts of metallic impactors onto Solar System bodies, including LCROSS impacting the Moon, iron meteorites onto Mars and NASA's "Deep Impact" mission where a spacecraft impacted a comet.

  1. A comparison of finite element analysis to smooth particle hydrodynamics for application to projectile impact on cementitious material

    Science.gov (United States)

    Nordendale, Nikolas A.; Heard, William F.; Sherburn, Jesse A.; Basu, Prodyot K.

    2016-03-01

    The response of structural components of high-strength cementitious (HSC) materials to projectile impact is characterized by high-rate fragmentation resulting from strong compressive shock waves coupled with reflected tensile waves. Accurate modeling of armor panels of such brittle materials under high-velocity projectile impact is a complex problem requiring meticulous experimental characterization of material properties. In a recent paper by the authors, an approach to handle such problems based on a modified Advanced Fundamental Concrete (AFC) constitutive model was developed. In the HSC panels considered in this study, an analogous approach is applied, and the predictions are verified with ballistic impact test data. Traditional Lagrangian finite element analysis (FEA) of these problems tends to introduce errors and suffers from convergence issues resulting from large deformations at free surfaces. Also, FEA cannot properly account for the issues of secondary impact of spalled fragments when multiple armor panels are used. Smoothed particle hydrodynamics (SPH) is considered to be an attractive alternative to resolve these and other issues. However, SPH-based quantitative results have been found to be less accurate than the FEA-based ones when the deformations are not sufficiently large. This paper primarily focuses on a comparison of FEA and SPH models to predict high-velocity projectile impact on single and stacked HSC panels. Results are compared to recent ballistic experiments performed as a part of this research, and conclusions are drawn based on the findings.

  2. Study of high-speed interaction processes between fluoropolymer projectiles and aluminum-based targets

    Institute of Scientific and Technical Information of China (English)

    Evgeny A. KHMELNIKOV; Alexey V. STYROV; Konstantin V. SMAGIN; Natalia S. KRAVCHENKO; Valery L. RUDENKO; Vladimir I. FALALEEV; Sergey S. SOKOLOV; Artem V. SVIDINSKY; Natalia F. SVIDINSKAYA

    2015-01-01

    The experimental results and numerical modeling of penetration process of fluoropolymer projectiles in aluminum-based targets are pre-sented. Analysis of mathematical models for interaction of elastoplastic projectile and target without taking additional energy released during interaction of fluoropolymer and aluminum into consideration is carried out. Energy fraction which is spent effectively on the increase in cavity volume is determined. The experimental and calculated results of penetration by combined and inert projectiles are compared.

  3. Mathematical Model to Simulate the Trajectory Elements ofan Artillery Projectile Proof Shot

    OpenAIRE

    K.K. Chand; H.S. Panda

    2007-01-01

    In external ballistics of a conventional spin-stabilised artillery projectile, there are a numberof trajectory models developed for computing trajectory elements having varying degrees ofcomplexity. The present study attempts to propose a single mathematical model, viz., simplifiedpoint-mass/simple particle trajectory model to simulate the trajectory elements of a typical spin-stabilised flat-head artillery projectile proof shot. Due to difficulties in the projectile shape andsize, and the co...

  4. Fragmentation of armor piercing steel projectiles upon oblique perforation of steel plates

    OpenAIRE

    Aizik F.; Ran E.; Vizel A.; Weiss A.; Paris V.

    2012-01-01

    In this study, a constitutive strength and failure model for a steel core of a14.5 mm API projectile was developed. Dynamic response of a projectile steel core was described by the Johnson-Cook constitutive model combined with principal tensile stress spall model. In order to obtain the parameters required for numerical description of projectile core material behavior, a series of planar impact experiments was done. The parameters of the Johnson-Cook constitutive model were extracted by match...

  5. Mass spectrometric analysis with cluster projectiles and coincidence counting

    Energy Technology Data Exchange (ETDEWEB)

    Cox, B.D.

    1992-01-01

    Methods for maximizing the amount of secondary ion information, per primary projectile, are described. The method is based on time-of-flight mass spectrometry and event-by-event coincidence counting. The information obtained from coincidence counting time-of-flight mass spectrometry includes: (a) surface composition, (b) relative concentrations, and (c) degree of intermolecular mixing. The technique was applied to the study of an important new class of polymers: polymer blends. Secondary ion mass spectrometry, when applied to the analysis of synthetic polymers, induces backbone fragmentation which is characteristic of the homopolymer. The characteristic fingerprint peaks from polystyrene and poly(vinyl methyl ether) were used to identify the presence of these two polymers in a polymer blend. The percent coincidence between the characteristic secondary ions from each component of the blend were used to determine both the relative concentration and the degree of molecular mixing. Results indicate molecular segregation of the two polymers on the film surface. The largest degree of segregation was determined for the phase separated blends. The performance of this technique depends on the desorption efficiency of the primary projectiles. In practice one seeks primary ions which are surface sensitive, have controllable parameters such as size, velocity, and charge state, and generate high secondary ion yields. Focus was placed on the use of keV organic cluster projectiles to meet these criteria. Of interest to this study were C[sub 18] (chrysene), C[sub 24] (coronene), and C[sub 60] (buckminster-fulleren). Results indicate enhanced secondary ion yields for C[sub 60]. For example, when CsI is bombarded with 30 keV C[sub 60], the yields for I[sup [minus

  6. Calculation of forces arising from impacting projectiles upon yielding structures

    International Nuclear Information System (INIS)

    Calculations concerning the impact of airplanes upon nuclear power plant buildings usually imply that the building 'acts' as a rigid target. This assumption is justified for considerations concerning the structural integrity of the building being hit. However, for investigating induced vibrations of components within the structure, this approach might -in general- be too conservative. It is expected, that yielding of the structure during impact reduces the peak values of the loads and changes the temporal behavior of the load function which is obtained for a rigid target. To calculate the changes of the load function which are due to deformations of the structure, Riera's method is extended for the case of a yielding target. In view of the applications of the calculations to the impact of airplanes upon buildings which are constructed to withstand loads of this kind without serious damage and without large deformations, it is possible to simplify the calculations to some extent. That is, the investigations need not take into account in detail the behavior of the target during impact. The calculations are performed with a one-dimensional model for the projectile. The direction of impact is perpendicular to the target surface; direction of impact and projectile axis coincide. The calculations were performed for several initial velocities of the projectiles simulating a fast flying military airplane. Variations of the peak values of the load functions as compared to corresponding values for a rigid target do not exceed about 10%. The overall temporal behavior of the load curves turns out to be not very sensitive to the yielding of the target, though, in some cases displacements in time of the peak positions within a single load curve do arise

  7. Aspects of nuclear collectivity studied in projectile Coulomb excitation experiments

    OpenAIRE

    Möller, Thomas

    2014-01-01

    Projectile Coulomb excitation experiments have been performed on the nuclei 130,132Ba, 154Sm, and 194,196Pt. A detailed description of the experiments and the data analysis is given. The results on absolute decay rates of the low-lying collective states of these nuclei allow for a comparison with predictions from different theoretical models of nuclear quadrupole collectivity. For the nucleus 154Sm the data on the decay rates of the states of the first K=0 band support the assignment of this ...

  8. Ionization of water molecules by fast charged projectiles

    International Nuclear Information System (INIS)

    Single-ionization cross sections of water molecules colliding with fast protons are calculated from lowest-order perturbation theory by taking all electrons and molecular orientations consistently into account. Explicit analytical formulas based on the peaking approximation are obtained for differential ionization cross sections with the partial contribution from the various electron orbitals accounted for. The results, which are in very good agreement with total and partial cross sections at high electron and projectile energies, display a strong variation on molecular orientation and molecular orbitals.

  9. Impact Features and Projectile Residues in Aerogel Exposed on Mir

    Science.gov (United States)

    Hörz, F.; Zolensky, M. E.; Bernhard, R. P.; See, T. H.; Warren, J. L.

    2000-10-01

    Approximately 0.63 m 2 of SiO 2-based aerogel (0.02 g cm -3) was exposed for 18 months on the Mir Station to capture hypervelocity particles from both man-made and natural sources. Optical inspection revealed two major classes of hypervelocity impact features in the aerogel: (1) long, carrot-shaped tracks, well known from laboratory impact experiments, that exhibit a depth- ( t) to-diameter ( D) relationship of t/ D>10, typically 20-30, and (2) shallow pits ( t/ DBlunt-nosed, yet deep ( t/ D=5-10), cylindrically shaped cavities suggest the existence of transitional morphologies between these tracks and pits. All tracks contain projectile residues that are unmelted, while pits rarely contain even traces of projectile material. These and other observations suggest that slender tracks form at lower impact velocities than the shallow pits. In addition, we observed that the measured track-length does not systematically correlate with the size of the projectile residue. This renders the reconstruction of encounter velocity and/or projectile mass from measured track dimensions not feasible at present. Recovery of particles from individual tracks is time-consuming, yet readily accomplished by operators familiar with the handling of individual, micrometer-sized particles. Compositional analyses by SEM-EDS identified a variety of man-made and natural particles. A few natural particles were embedded in epoxy, microtomed, and analyzed by TEM. All were polymineralic aggregates that contained olivine exhibiting sharp electron-diffraction spots, and suggesting that the materials had experienced only minimal shock-deformation, if any. One natural particle contained olivine, augite, diopside, troilite, chromite/magnetite, and hercynite, the latter existing as pristine, undeformed octahedral crystals. The olivine in two of the particles were Fo 60-70 and Fo 39-53, and thus, more equilibrated than olivines in most stratospheric particles (Fo 80-100). These results illustrate that

  10. Numerical Investigation of Penetration Performance of Non-Ideal Segmented-Rod Projectiles

    Institute of Scientific and Technical Information of China (English)

    ALY S Y; LI Q M

    2008-01-01

    The design of a segmented-rod projectile is often simplified into an ideal one in theoretical analysis for the convenience of modeling of its performance.But the actual performance of non-ideal segmented-rod projectiles over the impact velocity range in practical applications was rarely explored.AUTODYN numerical code is used to investigate the influence of the component design upon the penetration performance of non-ideal segmented-rod projectiles over a wide range of impact velocities, which can be used to guide the optimal design of weaponry segmented-rod projectiles.

  11. Features of transformation of water projectiles moving through high-temperature combustion products

    Science.gov (United States)

    Volkov, R. S.; Zabelin, M. V.; Kuznetsov, G. V.; Strizhak, P. A.

    2016-03-01

    Results of an experimental investigation of transformation of water projectiles (spherical "balls" with a volume of 50-1000 mL) in the course of their free fall (from a height of 3 m) within a high-temperature (about 1100 K) gaseous medium (with the application of the standardized fire) are represented. Investigations are carried out for projectiles of water, its solutions with NaCl, and suspensions with carbon particles. Conditions and characteristics of disruption of projectiles are determined as they move through high-temperature gases. The transformation deceleration of the projectile was revealed because of its "compression" in the high-temperature zone (in comparison with moderate temperatures).

  12. Chemical modification of projectile residues and target material in a MEMIN cratering experiment

    Science.gov (United States)

    Ebert, Matthias; Hecht, Lutz; Deutsch, Alexander; Kenkmann, Thomas

    2013-01-01

    In the context of the MEMIN project, a hypervelocity cratering experiment has been performed using a sphere of the iron meteorite Campo del Cielo as projectile accelerated to 4.56 km s-1, and a block of Seeberger sandstone as target material. The ejecta, collected in a newly designed catcher, are represented by (1) weakly deformed, (2) highly deformed, and (3) highly shocked material. The latter shows shock-metamorphic features such as planar deformation features (PDF) in quartz, formation of diaplectic quartz glass, partial melting of the sandstone, and partially molten projectile, mixed mechanically and chemically with target melt. During mixing of projectile and target melts, the Fe of the projectile is preferentially partitioned into target melt to a greater degree than Ni and Co yielding a Fe/Ni that is generally higher than Fe/Ni in the projectile. This fractionation results from the differing siderophile properties, specifically from differences in reactivity of Fe, Ni, and Co with oxygen during projectile-target interaction. Projectile matter was also detected in shocked quartz grains. The average Fe/Ni of quartz with PDF (about 20) and of silica glasses (about 24) are in contrast to the average sandstone ratio (about 422), but resembles the Fe/Ni-ratio of the projectile (about 14). We briefly discuss possible reasons of projectile melting and vaporization in the experiment, in which the calculated maximum shock pressure does not exceed 55 GPa.

  13. Rupture of Human Skin Membrane under Impact of Parabolodial Projectile: Bullet wound Ballistics

    Directory of Open Access Journals (Sweden)

    M. Mukhtar Ali

    1996-10-01

    Full Text Available This paper attempts to study the effect of the impact of a paraboloidal projectile on human shin membrane. The tip of the projectile (i.e., the bullet tip has been considered to be paraboloidal and is made of lead or steel. The threshold velocity i.e., the velocity when the skin membrane is about to rupture has been calculated for human beings of various age groups. The threshold velocity for a paraboloidal projectile of certain dimensions has been found, for all age groups, to be less than that of a spherical projectile under similar conditions.

  14. Two source emission behaviour of alpha fragments of projectile having energy around 1 GeV per nucleon

    CERN Document Server

    Singh, V; Pathak, Ramji

    2010-01-01

    The emission of projectile fragments alpha has been studied in ^{84}Kr interactions with nuclei of the nuclear emulsion detector composition at relativistic energy below 2 GeV per nucleon. The angular distribution of projectile fragments alpha in terms of transverse momentum could not be explained by a straight and clean-cut collision geometry hypothesis of Participant - Spectator (PS) Model. Therefore, it is assumed that projectile fragments alpha were produced from two separate sources that belong to the projectile spectator region differing drastically in their temperatures. It has been clearly observed that the emission of projectile fragments alpha are from two different sources. The contribution of projectile fragments alpha from contact layer or hot source is a few percent of the total emission of projectile fragments alphas. Most of the projectile fragments alphas are emitted from the cold source. It has been noticed that the temperature of hot and cold regions are dependent on the projectile mass num...

  15. Electron capture by metastable projectiles on He and Ne

    International Nuclear Information System (INIS)

    Electron capture to n> or =2 levels of F7+ (1s2s) 3S projectiles lead to three-electron ions with an energetically allowed K-Auger decay channel. We have measured the F K-Auger emission spectra for collisions with thin gas targets of He and Ne with sufficiently high resolution to distinguish capture to several of the low-lying n values. The K-Auger production cross sections are reported as a function of the n level into which the electron is captured. The n-level dependence is measured for projectile energies of 6, 9, 12, and 15 MeV and is compared to the Oppenheimer-Brinkman-Kramers OBK model for charge transfer and to a 1/n3 function. The measured K-Auger electron-production cross sections closely follow the 1/n3 function which differs from the predicted OBK n dependence, even though the cross sections for the higher n levels agree with the predicted OBK energy dependence. The effects of cascading upon the calculated n dependence are also studied

  16. Projectile charge state dependent sputtering of solid surfaces

    CERN Document Server

    Hayderer, G

    2000-01-01

    dependence on the ion kinetic energy. This new type of potential sputtering not only requires electronic excitation of the target material, but also the formation of a collision cascade within the target in order to initiate the sputtering process and has therefore been termed kinetically assisted potential sputtering. In order to study defects induced by potential sputtering on the atomic scale we performed measurements of multiply charged Ar ion irradiated HOPG (highly oriented pyrolitic graphite) samples with scanning tunneling microscopy (STM). The only surface defects found in the STM images are protrusions. The mean diameter of the defects increases with projectile charge state while the height of the protrusions stays roughly the same indicating a possible pre-equilibrium effect of the stopping of slow multiply charged projectiles in HOPG. Total sputter yields for impact of slow singly and multiply charged ions on metal- (Au), oxide- (Al2O3, MgO) and alkali-halide surfaces (LiF) have been measured as a...

  17. Shock initiation thresholds for projectiles with curved surfaces

    International Nuclear Information System (INIS)

    The impacts of flat-nosed rods into bare conventional high explosives tend to produce either detonations or very little discernable reaction. In contrast impacts from projectiles with curved striking surfaces, such as round-nosed rods, can produce a range of reactions, some very vigorous, as well as detonations. The current work attempts to explain this complex behaviour. The identification of a predictive threshold as corresponding to the boundary of sub-detonic reactions for low pressure impacts, rather than the boundary between no reaction and detonation, is discussed in the light of experimental results. The structure of the impact shock is explored and the existence of two sonic boundaries is explained. The linkage between the theoretical initiation threshold and one of these sonic boundaries is obtained and the implications of this threshold in terms of the proportion of the diameter of the projectile needed to cause initiation are discussed and the results illustrated using CREST, a hydrocode-based reactive-burn explosive model.

  18. Reaction dynamics of {sup 34-38}Mg projectile with carbon target using Glauber model

    Energy Technology Data Exchange (ETDEWEB)

    Shama, Mahesh K., E-mail: maheshphy82@gmail.com [School of Physics and Material Sciences, Thapar University Patiala-147004 (India); Department of Applied Sciences, Chandigarh Engineering College, Landran Mohali-140307 (India); Panda, R. N. [Department of Physics, ITER, Shiksha O Anusandhan University, Bhubaneswar-751030 (India); Sharma, Manoj K. [School of Physics and Material Sciences, Thapar University Patiala-147004 (India); Patra, S. K. [Institute of Physics, Sachivalaya marg Bhubneswar-751005 (India)

    2015-08-28

    We have studied nuclear reaction cross-sections for {sup 34-38}Mg isotopes as projectile with {sup 12}C target at projectile energy 240AMeV using Glauber model with the conjunction of densities from relativistic mean filed formalism. We found good agreement with the available experimental data. The halo status of {sup 37}Mg is also investigated.

  19. Comment on "The motion of an arbitrarily rotating spherical projectile and its application to ball games"

    DEFF Research Database (Denmark)

    Jensen, Jens Højgaard

    2014-01-01

    independent of the Reynolds number and proportional to the square of the projectile's velocity. In this paper, by dimensional analysis, the latter assumption is shown to be incorrect for forces dependent on the angular velocity of the projectile, e.g. the lift force....

  20. Treatment of Ion-Atom Collisions Using a Partial-Wave Expansion of the Projectile Wavefunction

    Science.gov (United States)

    Wong, T. G.; Foster, M.; Colgan, J.; Madison, D. H.

    2009-01-01

    We present calculations of ion-atom collisions using a partial-wave expansion of the projectile wavefunction. Most calculations of ion-atom collisions have typically used classical or plane-wave approximations for the projectile wavefunction, since partial-wave expansions are expected to require prohibitively large numbers of terms to converge…

  1. Deformation and Melting of Iron-Rich Projectiles in Hypervelocity MEMIN Cratering Experiments

    Science.gov (United States)

    Kenkmann, T.; Ebert, M.; Trullenque, G.; Deutsch, A.; Hecht, L.; Salge, T.; Schäfer, F.; Thoma, K.

    2013-09-01

    We conducted 23-54 kJ impact experiments using projectiles composed of steel and iron meteorite Campo del Cielo to study the structural changes that occur upon impact in these projectiles. Extensive melting is largely the result of plastic deformation.

  2. Light-particle multiplicity accompanying projectile breakup at 20 MeV/A

    International Nuclear Information System (INIS)

    A large-solid-angle array has been used to determine the multiplicity of Z = 1 and Z = 2 particles accompanying projectile breakup into two fragments each with 5 ≤ Z ≤ 8. The charge balance obtained shows that projectile breakup is not associated with an unusual charge transfer to the target. 13 refs., 1 fig

  3. Gamma ray nondestructive inspection of local TNT density in cannon projectile casing

    International Nuclear Information System (INIS)

    The effects of various parameters on measuring TNT densities in cannon projectile casing were discussed. The density measurement was performed by using the concept of equivalent physical absorption thickness, the technological process of flooding water into projectile casing, and the nondestructive inspecting formula deduced on gamma-ray transmission and flooding method

  4. Reaction dynamics of 34-38Mg projectile with carbon target using Glauber model

    International Nuclear Information System (INIS)

    We have studied nuclear reaction cross-sections for 34-38Mg isotopes as projectile with 12C target at projectile energy 240AMeV using Glauber model with the conjunction of densities from relativistic mean filed formalism. We found good agreement with the available experimental data. The halo status of 37Mg is also investigated

  5. Correlations between projectile and target break-up in intermediate and high energy heavy ion collisions

    International Nuclear Information System (INIS)

    16O induced reactions in nuclear emulsion have been studied at three different energies 75, 175 and 2000 MeV/A. The probability that the projectile is completely destroyed increases significantly with increasing beam energy. The charge sum of projectile fragments (Z>2) shows a strong odd-even effect favouring even values. Projectile fragments are strongly slowed down at 75 MeV/A, while at 175 MeV/A the result is consistent with 2.1 GeV/A fragmentation data. The downshift in rapidity increases with decreasing impact parameter. The transverse momenta of projectile fragments are larger at 75 MeV/A than at higher energies, showing important deflections in the Coulomb field. The target disintegration depends on the transverse momentum of the projectile fragment. (Author)

  6. The terminal effects of chisel-shape projectile penetrating into metallic target plates

    Science.gov (United States)

    Tao, Xu; Yao, Xiaohu; Ma, Wei

    2015-09-01

    This work performs the analysis and simulation investigations of penetration behaviors of chisel-shape projectile. In analysis, the projectile is assumed to be a rigid body and the target plate is elastic-plastic material. By introducing the velocity potential function, the velocity field in target is first obtained. Then, the momentum equation is solved for determining the pressure and stress fields in the elastic and plastic regions in target. The variation of the resultant force subjected by the projectiles with the penetration depth is studied. The approximate expressions of penetration depth and the residual velocity with the initial impacting velocity are obtained for the exploration of the penetration mechanisms of the chisel-shape projectile. In numerical simulation, the main attention focuses on the dissipation mechanisms of the kinetic energy of the chisel-shape projectile in penetration process.

  7. Adaptive Finite-element Analysis of Plastic Deformation of Plates under Projectile Impact

    Directory of Open Access Journals (Sweden)

    T. Prakash

    2003-01-01

    Full Text Available This paper deals with the finite-element analysis of plastic deformation of plates during normal impact of projectile on plates, The finite element method implemented here is based on the flow formulation of plasticity. During projectile impact the geometrical configuration of domain is progressively altered that generally causes distortion of mesh. It affects the accuracy of finite-element solution, Hence, a posteriori error estimation for the computed finite-element solution has been incorporated to capture the zones of high stress and strain gradients. The h-refinement of the mesh is carried out over such domain to limit the solution error, Two projectile impact problems on a circular aluminium plate-one by a blunt-end projectile and another by a hemi-spherical-headed projectile-are analysed to illustrate the proposed method.

  8. Instantaneous charge state of Uranium projectiles in fully ionized plasmas from energy loss experiments

    CERN Document Server

    Morales, Roberto; Casas, David

    2016-01-01

    The instantaneous charge state of uranium ions traveling through a fully ionized hydrogen plasma has been theoretically studied and compared with one of the first energy loss experiments in plasmas, carried out at GSI-Darmstadt by Hoffmann \\textit{et al.} in the 90's. For this purpose, two different methods to estimate the instantaneous charge state of the projectile have been employed: (1) rate equations using ionization and recombination cross sections, and (2) equilibrium charge state formulas for plasmas. Also, the equilibrium charge state has been obtained using these ionization and recombination cross sections, and compared with the former equilibrium formulas. The equilibrium charge state of projectiles in plasmas is not always reached, it depends mainly on the projectile velocity and the plasma density. Therefore, a non-equilibrium or an instantaneous description of the projectile charge is necessary. The charge state of projectile ions cannot be measured, except after exiting the target, and experime...

  9. Two source emission behavior of projectile fragments alpha in 84^Kr interactions at around 1 GeV per nucleon

    CERN Document Server

    Singh, M K; Singh, V

    2010-01-01

    The emission of projectile fragments alpha has been studied in 84^Kr interactions with nuclei of the nuclear emulsion detector composition at relativistic energy below 2 GeV per nucleon. The angular distribution of projectile fragments alpha in terms of transverse momentum could not be explained by a straight and clean-cut collision geometry hypothesis of Participant - Spectator (PS) Model. Therefore, it is assumed that projectile fragments alpha were produced from two separate sources that belong to the projectile spectator region differing drastically in their temperatures. It has been clearly observed that the emission of projectile fragments alpha are from two different sources. The contribution of projectile fragments alpha from contact layer or hot source is a few percent of the total emission of projectile fragments alphas. Most of the projectile fragments alphas are emitted from the cold source.

  10. Finite Element Modeling of Transient Temperatures in a Small-Caliber Projectile

    Directory of Open Access Journals (Sweden)

    M. B. Thomas

    2010-01-01

    Full Text Available Problem statement: Future generations of intelligent munitions will use Microelectromechanical Systems (MEMS for guidance, fuzing logic and assessment of the battlefield environment. The temperatures fund in a gun system, however, are sufficient to damage some materials used in the fabrication of MEMS. The motivation of this study is to model the dynamic temperature distribution in a typical small-caliber projectile. Approach: An axisymmetric finite-element model of a projectile is developed to simulate temperatures through internal ballistics (the projectile is in the gun barrel and external ballistics (the projectile travels in a free trajectory towards the target. Accuracy of the simulation is confirmed through comparison to analytical models and to payloads attached to experimental projectiles. In the simulation, the exact values for some boundary conditions are unknown and/or unknowable. A sensitivity analysis determines the effect of these uncertain parameters. Results: The simulation shows that friction at the projectile-gun barrel interface is primarily responsible for elevated temperatures in a gun system. Other factors have much smaller effects. The short duration of the internal ballistics prevents the frictional heat from diffusing into the bulk of the projectile. As a result, the projectile has a shallow, high-temperature zone at its bearing surface as it leaves the gun barrel. During external ballistics, this heat will diffuse through the projectile, but most of the projectile experiences temperatures of 56°C or lower. Simulation shows that the polymer package around a MEMS device will further attenuate heat flow, limiting temperatures in the device to less than 30°C. Conclusion: The finite element model demonstrates that a MEMS device may be engineered to survive temperatures expected in the ballistic environment.

  11. Identification of very exotic nuclei produced by projectile fragmentation

    International Nuclear Information System (INIS)

    This work is devoted to the production and identification of neutron rich nuclei, far from the valley of stability. These nuclei are produced by fragmentation of 40Ar (44 MeV/u) and 86Kr (33MeV/u) projectiles produced by the GANIL facility, on tantalum and titanium targets. Reaction products, collected at 00, are analysed by the LISE spectrometer. In the first experiment (40Ar beam) the following isotopes were observed for the first time 23N, 29Ne and 30Ne and the non stability of 18B, 21C and 25O was established. In a second experiment (86Kr beam) a lot of new nuclides have been observed for the first time, namely: 47Ar, 54Sc, 59V,60V, 61Cr,62Cr, 64Mn,65Mn, 66Fe,67Fe, 68Fe and 68Co, 71Co

  12. Aerodynamic Jump: A Short Range View for Long Rod Projectiles

    Directory of Open Access Journals (Sweden)

    Mark Bundy

    2001-01-01

    Full Text Available It is shown that aerodynamic jump for a nonspinning kinetic energy penetrator is not – as conventional definitions may infer – a discontinuous change in the direction of motion at the origin of free flight, nor is it the converse, a cumulative redirection over a domain of infinite extent. Rather, with the aid of an alternative kinematical definition, it is shown that aerodynamic jump for such a projectile is a localized redirection of the center-of-gravity motion, caused by the force of lift due to yaw over the relatively short region from entry into free flight until the yaw reaches its first maximum. A rigorous proof of this statement is provided, but the primary objective of this paper is to provide answers to the questions: what is aerodynamic jump, what does it mean, and what aspects of the flight trajectory does it refer to, or account for.

  13. Influence of projectile α-breakup threshold on complete fusion

    International Nuclear Information System (INIS)

    Complete fusion excitation functions for B11,10+Tb159 have been measured at energies around the respective Coulomb barriers, and the existing complete fusion measurements for Li7+Tb159 have been extended to higher energies. The measurements show significant reduction of complete fusion cross sections at above-barrier energies for both the reactions, B10+Tb159 and Li7+Tb159, when compared to those for B11+Tb159. The comparison shows that the extent of suppression of complete fusion cross sections is correlated with the α-separation energies of the projectiles. Also, the two reactions, B10+Tb159 and Li7+Tb159 were found to produce incomplete fusion products at energies near the respective Coulomb barriers, with the α-particle emitting channel being the favoured incomplete fusion process in both the cases

  14. Influence of projectile - breakup threshold on complete fusion

    CERN Document Server

    Mukherjee, A; Pradhan, M K; Sarkar, M S; Basu, P; Dasmahapatra, B; Bhattacharya, T; Bhattacharya, S; Basu, S K; Chatterjee, A; Tripathi, V; Kailas, S; Roy, Subinit

    2006-01-01

    Complete fusion excitations for 11,10B+159Tb have been measured at energies around the respective Coulomb barriers, and the existing complete fusion measurements for 7Li+159Tb have been extended to higher energies. The measurements show significant reduction of complete fusion cross sections at above-barrier energies for both the reactions, 10B+159Tb and 7Li+159Tb, when compared to those for 11B+159Tb. The comparison shows that the extent of suppression of complete fusion cross sections is correlated with the -separation energies of the projectiles. Also, the two reactions, 10B+159Tb and 7Li+159Tb were found to produce incomplete fusion products at energies near the respective Coulomb barriers, with the - particle emitting channel being the favoured incomplete fusion process in both the cases.

  15. Projectile dependency of radioactivities of spallation products induced in copper

    Energy Technology Data Exchange (ETDEWEB)

    Yashima, Hiroshi; Sugita, Hiroshi; Nakamura, Takashi; Shiomi, Tomoyuki [Tohoku Univ., Department of Quantum Science and Energy Engineering, Sendai, Miyagi (Japan); Uwamino, Yoshitomo; Ito, Sachiko [Institute of Physical and Chemical Research, Wako, Saitama (Japan); Fukumura, Akifumi [National Institute of Radiological Sciences, Chiba (Japan)

    2001-03-01

    The reaction cross-sections of spallation products in a Cu target by 230 MeV/nucleon Ne, C, He, p and 100 MeV/nucleon Ne, C ions were obtained. Irradiation experiments were performed at HIMAC (Heavy Ion Medical Accelerator in Chiba), National Institute of Radiological Sciences. Gamma-ray spectra from activation samples were measured with an HPGe detector. >From the gamma-ray spectra, we obtained the variation of reaction cross sections of Cl-38, Cr-49, Mn-55, Cu-60, Cu-61 and Co-62m in Cu sample with Cu target thickness and mass-yield distribution of nuclides in Cu sample on the surface of Cu target. The results showed that the dependence of the cross-sections to the projectile mass varies with the mass number difference between Cu and produced nuclide. (author)

  16. Expert Systems Aimed at General Design of Projectiles

    Institute of Scientific and Technical Information of China (English)

    YUAN Zhi-hua; HOU Ni-na; HU Yu-hui

    2007-01-01

    Expert systems aimed at the general design of projectiles can implement a series of intelligent designs, such as the design of HE shell, the scheme expounded and proved, the emulation analysis and calculation, etc. Aiming at the product design feature, the expert system adopts the object-oriented knowledge representation and all kinds of inference control engines to describe and reason the relevant knowledge regarding the product through the microcomputer. It embodies the foundation of emulation analysis and simulated manufacturing of the shell. It makes use of the method that knowledge expression is combined with condition of inference to carry out the overall design and emulation and reference.The paper gives the ways through which the functions can be achieved, gives the modularization of reference and the design methods of systematization, puts forward the method of knowledge expression and working interface, and supplies a platform for similar products of the shell category that can be quickly designed.

  17. Breakup conditions of projectile spectators from dynamical observables

    Energy Technology Data Exchange (ETDEWEB)

    Begemann-Blaich, M.; Lindenstruth, V.; Pochodzalla, J. [and others

    1998-03-01

    Momenta and masses of heavy projectile fragments (Z {>=} 8), produced in collisions of {sup 197}Au with C, Al, Cu and Pb targets at E/A=600 MeV, were determined with the ALADIN magnetic spectrometer at SIS. Using these informations, an analysis of kinematic correlations between the two and three heaviest projectile fragments in their rest frame was performed. The sensitivity of these correlations to the conditions at breakup was verified within the schematic SOS-model. For a quantitative investigation, the data were compared to calculations with statistical multifragmentation models and to classical three-body calculations. With classical trajectory calculations, where the charges and masses of the fragments are taken from a Monte Carlo sampling of the experimental events, the dynamical observables can be reproduced. The deduced breakup parameters, however, differ considerably from those assumed in the statistical multifragmentation models which describe the charge correlations. If, on the other hand, the analysis of kinematic and charge correlations is performed for events with two and three heavy fragments produced by statistical multifragmentation codes, a good agreement with the data is found with the exception that the fluctuation widths of the intrinsic fragment energies are significantly underestimated. A new version of the multifragmentation code MCFRAG was therefore used to investigate the potential role of angular momentum at the breakup stage. If a mean angular momentum of 0.75 {Dirac_h}/nucleon is added to the system, the energy fluctuations can be reproduced, but at the same time the charge partitions are modified and deviate from the data. (orig.)

  18. Investigations of nuclear projectile break-up reactions

    International Nuclear Information System (INIS)

    The cross sections for radiative capture of α-particles, deuterons and protons by light nuclei at very low relative energies are of particular importance for the understanding of the nucleosynthesis of chemical elements and for determining the relative elemental abundances in stellar burning processes at various astrophysical sites. As example we quote the reactions α+d → 6Li+γ, α+3He → 7Be+γ, or α+12C → 16O+γ. As an alternative to the direct experimental study of these processes we consider the inverse process, the photodisintegration, by means of the virtual photons provided by a nuclear Coulomb field: Z+a → Z+b+c. The radiative capture process b+c → a+γ is related to the inverse process, the photodisintegration γ+a → b+c by the detailed balance theorem. Except for the extreme case very close to the threshold the phase space favours the photodisintegration cross section as compared to the radiative capture. The Coulomb dissociation cross section proves to be enhanced due to the large virtual photon number, seen by the passing projectile, and the kinematics of the process leads to particular advantages for studies of the interaction of the two break-up fragments at small relative energies Ebc. The conditions of dedicated experimental investigations are discussed and demonstrated by recent experimental and theoretical studies of the break-up of 156 MeV 6Li projectiles. In addition, a brief review about general features of break-up processes of light ions in the field of atomic nuclei is given. (orig.)

  19. Breakup conditions of projectile spectators from dynamical observables

    International Nuclear Information System (INIS)

    Momenta and masses of heavy projectile fragments (Z ≥ 8), produced in collisions of 197Au with C, Al, Cu and Pb targets at E/A=600 MeV, were determined with the ALADIN magnetic spectrometer at SIS. Using these informations, an analysis of kinematic correlations between the two and three heaviest projectile fragments in their rest frame was performed. The sensitivity of these correlations to the conditions at breakup was verified within the schematic SOS-model. For a quantitative investigation, the data were compared to calculations with statistical multifragmentation models and to classical three-body calculations. With classical trajectory calculations, where the charges and masses of the fragments are taken from a Monte Carlo sampling of the experimental events, the dynamical observables can be reproduced. The deduced breakup parameters, however, differ considerably from those assumed in the statistical multifragmentation models which describe the charge correlations. If, on the other hand, the analysis of kinematic and charge correlations is performed for events with two and three heavy fragments produced by statistical multifragmentation codes, a good agreement with the data is found with the exception that the fluctuation widths of the intrinsic fragment energies are significantly underestimated. A new version of the multifragmentation code MCFRAG was therefore used to investigate the potential role of angular momentum at the breakup stage. If a mean angular momentum of 0.75 ℎ/nucleon is added to the system, the energy fluctuations can be reproduced, but at the same time the charge partitions are modified and deviate from the data. (orig.)

  20. A distorted-wave Born-approximation theory of heavy-ion induced projectile break-up reactions

    International Nuclear Information System (INIS)

    A distorted-wave Born-approximation (DWBA) formalism is developed to describe the 'elastic' and 'inelastic' break-up of the projectile in the heavy ion induced reactions. Using a 'local momentum approximation' and the surface localization property of these reactions expressions for the DWBA transition amplitude are derived. One of the attractive features of the present formulation is the fact that the readial integrals involved in it are the same as those contained in the transition amplitude evaluated with a zero range approximation. The validity of the approximations used in our derivations has been tested and it is shown that these approximations are well fulfilled. (orig.)

  1. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    Science.gov (United States)

    Kruszka, L.; Magier, M.

    2012-08-01

    The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity) in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with the phenomena of gunshot and terminal ballistics it's particularly important to develop a model of strength and armour penetration with KE projectile founded on reliable results of dynamic experiments and constituting the base for further analyses and optimization of projectile designs in order to achieve required penetration depth. Static and dynamic results of strength investigations of the EN AW-7012 aluminium alloy (sabot) and tungsten alloy (penetrator) are discussed in this paper. Static testing was carried out with the INSTRON testing machine. Dynamic tests have been conducted using the split Hopkinson pressure bars technique at strain rates up to 1,2 ṡ 104s-1 (for aluminium alloy) and 6 ṡ 103s-1 (for tungsten alloy).

  2. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    Directory of Open Access Journals (Sweden)

    Magier M.

    2012-08-01

    Full Text Available The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with the phenomena of gunshot and terminal ballistics it’s particularly important to develop a model of strength and armour penetration with KE projectile founded on reliable results of dynamic experiments and constituting the base for further analyses and optimization of projectile designs in order to achieve required penetration depth. Static and dynamic results of strength investigations of the EN AW-7012 aluminium alloy (sabot and tungsten alloy (penetrator are discussed in this paper. Static testing was carried out with the INSTRON testing machine. Dynamic tests have been conducted using the split Hopkinson pressure bars technique at strain rates up to 1,2 ⋅ 104s−1 (for aluminium alloy and 6 ⋅ 103s−1 (for tungsten alloy.

  3. A Method for Guiding a Salvo of guided Projectiles to a Target, a System and a Computer Program Product

    NARCIS (Netherlands)

    Ruizenaar, M.G.A.

    2011-01-01

    The invention relates to a method of guiding a salvo of guided projectiles to a target. The method comprises the steps of generating a beam defining a common reference coordinate system, determining the position of each projectile relative to the beam, and providing to each projectile: position info

  4. High-speed Imaging of Global Surface Temperature Distributions on Hypersonic Ballistic-Range Projectiles

    Science.gov (United States)

    Wilder, Michael C.; Reda, Daniel C.

    2004-01-01

    The NASA-Ames ballistic range provides a unique capability for aerothermodynamic testing of configurations in hypersonic, real-gas, free-flight environments. The facility can closely simulate conditions at any point along practically any trajectory of interest experienced by a spacecraft entering an atmosphere. Sub-scale models of blunt atmospheric entry vehicles are accelerated by a two-stage light-gas gun to speeds as high as 20 times the speed of sound to fly ballistic trajectories through an 24 m long vacuum-rated test section. The test-section pressure (effective altitude), the launch velocity of the model (flight Mach number), and the test-section working gas (planetary atmosphere) are independently variable. The model travels at hypersonic speeds through a quiescent test gas, creating a strong bow-shock wave and real-gas effects that closely match conditions achieved during actual atmospheric entry. The challenge with ballistic range experiments is to obtain quantitative surface measurements from a model traveling at hypersonic speeds. The models are relatively small (less than 3.8 cm in diameter), which limits the spatial resolution possible with surface mounted sensors. Furthermore, since the model is in flight, surface-mounted sensors require some form of on-board telemetry, which must survive the massive acceleration loads experienced during launch (up to 500,000 gravities). Finally, the model and any on-board instrumentation will be destroyed at the terminal wall of the range. For these reasons, optical measurement techniques are the most practical means of acquiring data. High-speed thermal imaging has been employed in the Ames ballistic range to measure global surface temperature distributions and to visualize the onset of transition to turbulent-flow on the forward regions of hypersonic blunt bodies. Both visible wavelength and infrared high-speed cameras are in use. The visible wavelength cameras are intensified CCD imagers capable of integration

  5. The influence of aerodynamic coefficients on the elements of classic projectile paths

    Directory of Open Access Journals (Sweden)

    Damir D. Jerković

    2011-04-01

    Full Text Available The article deals with the results of the research on the influence of aerodynamic coefficient values on the trajectory elements and the stability parameters of classic axisymmetric projectiles. It presents the characteristic functions of aerodynamic coefficients with regard to aerodynamic parameters and the projectile body shape. The trajectory elements of the model of classic axisymmetric projectiles and the analyses of their changes were presented with respect to the aerodynamic coefficient values. Introduction Classic axisymmetric projectiles fly through atmosphere using muzzle velocity as initial energy resource, so the aerodynamic force and moment have the most significant influence on the motion of projectiles. The aerodynamic force and moment components represented as aerodynamic coefficients depend on motion velocity i. e. flow velocity, the flow features produced by projectile shape and position in the flow, and angular velocity (rate of the body. The functional dependence of aerodynamic coefficients on certain influential parameters, such as angle of attack and angular velocity components is expressed by the derivative of aerodynamic coefficients. The determination of aerodynamic coefficients and derivatives enables complete definition of the aerodynamic force and moment acting on the classic projectile. The projectile motion problem is considered in relation to defining the projectile stability parameters and the conditions under which the stability occurs. The comparative analyses of aerodynamic coefficient values obtained by numerical methods, semi empirical calculations and experimental research give preliminary evaluation of the quality of the determined values. The flight simulation of the motion of a classic axisymetric projectile, which has the shape defined by the aerodynamic coefficient values, enables the comparative analyses of the trajectory elements and stability characteristics. The model of the classic projectile

  6. Techniques for Transition and Surface Temperature Measurements on Projectiles at Hypersonic Velocities- A Status Report

    Science.gov (United States)

    Wilder, M. C.; Bogdanoff, D. W.

    2005-01-01

    A research effort to advance techniques for determining transition location and measuring surface temperatures on graphite-tipped projectiles in hypersonic flight in a ballistic range is described. Projectiles were launched at muzzle velocities of approx. 4.7 km/sec into air at pressures of 190-570 Torr. Most launches had maximum pitch and yaw angles of 2.5-5 degrees at pressures of 380 Torr and above and 3-6 degrees at pressures of 190-380 Torr. Arcjet-ablated and machined, bead-blasted projectiles were launched; special cleaning techniques had to be developed for the latter class of projectiles. Improved methods of using helium to remove the radiating gas cap around the projectiles at the locations where ICCD (intensified charge coupled device) camera images were taken are described. Two ICCD cameras with a wavelength sensitivity range of 480-870 nm have been used in this program for several years to obtain images. In the last year, a third camera, with a wavelength sensitivity range of 1.5-5 microns [in the infrared (IR)], has been added. ICCD and IR camera images of hemisphere nose and 70 degree sphere-cone nose projectiles at velocities of 4.0-4.7 km/sec are presented. The ICCD images clearly show a region of steep temperature rise indicative of transition from laminar to turbulent flow. Preliminary temperature data for the graphite projectile noses are presented.

  7. Geochemical processes between steel projectiles and silica-rich targets in hypervelocity impact experiments

    Science.gov (United States)

    Ebert, Matthias; Hecht, Lutz; Deutsch, Alexander; Kenkmann, Thomas; Wirth, Richard; Berndt, Jasper

    2014-05-01

    The possibility of fractionation processes between projectile and target matter is critical with regard to the classification of the impactor type from geochemical analysis of impactites from natural craters. Here we present results of five hypervelocity MEMIN impact experiments (Poelchau et al., 2013) using the Cr-V-Co-Mo-W-rich steel D290-1 as projectile and two different silica-rich lithologies (Seeberger sandstone and Taunus quartzite) as target materials. Our study is focused on geochemical target-projectile interaction occurring in highly shocked and projectile-rich ejecta fragments. In all of the investigated impact experiments, whether sandstone or quartzite targets, the ejecta fragments show (i) shock-metamorphic features e.g., planar-deformation features (PDF) and the formation of silica glasses, (ii) partially melting of projectile and target, and (iii) significant mechanical and chemical mixing of the target rock with projectile material. The silica-rich target melts are strongly enriched in the "projectile tracer elements" Cr, V, and Fe, but have just minor enrichments of Co, W, and Mo. Inter-element ratios of these tracer elements within the contaminated target melts differ strongly from the original ratios in the steel. The fractionation results from differences in the reactivity of the respective elements with oxygen during interaction of the metal melt with silicate melt. Our results indicate that the principles of projectile-target interaction and associated fractionation do not depend on impact energies (at least for the selected experimental conditions) and water-saturation of the target. Partitioning of projectile tracer elements into the silicate target melt is much more enhanced in experiments with a non-porous quartzite target compared with the porous sandstone target. This is mainly the result of higher impact pressures, consequently higher temperatures and longer reaction times at high temperatures in the experiments with quartzite as

  8. The Paradigm of Projectile Motion and its Consequences for Special Relativity. Making Sense of Physics

    CERN Document Server

    Klevgard, Paul A

    2015-01-01

    The classical (Newtonian) concept of projectile motion underwent a series of seemingly minor changes and adjustments between the discovery of the quantum (Planck, 1900) and the early codification of quantum theory (Dirac, 1928). The goal of physicists in this period was to keep change to a minimum and preserve as much as possible of the traditional projectile paradigm (TPP). These adjustments were successful in masking an all-out projectile paradigm crisis, but they have left us with a conceptual muddle. This has been especially deleterious for special relativity and our understanding of space contraction and time dilation.

  9. Rupture of Human Skin Membrane under Impact of Parabolodial Projectile: Bullet wound Ballistics

    OpenAIRE

    M. Mukhtar Ali; Vijay Paul Singh; GH. Nabi Parrey

    1996-01-01

    This paper attempts to study the effect of the impact of a paraboloidal projectile on human shin membrane. The tip of the projectile (i.e., the bullet tip) has been considered to be paraboloidal and is made of lead or steel. The threshold velocity i.e., the velocity when the skin membrane is about to rupture has been calculated for human beings of various age groups. The threshold velocity for a paraboloidal projectile of certain dimensions has been found, for all age groups, to be les...

  10. Projectile motion in real-life situation: Kinematics of basketball shooting

    Science.gov (United States)

    Changjan, A.; Mueanploy, W.

    2015-06-01

    Basketball shooting is a basic practice for players. The path of the ball from the players to the hoop is projectile motion. For undergraduate introductory physics courses student must be taught about projectile motion. Basketball shooting can be used as a case study for learning projectile motion from real-life situation. In this research, we discuss the relationship between optimal angle, minimum initial velocity and the height of the ball before the player shoots the ball for basketball shooting problem analytically. We found that the value of optimal angle and minimum initial velocity decreases with increasing the height of the ball before the player shoots the ball.

  11. Acceleration of small, light projectiles (including hydrogen isotopes) to high speeds using a two-stage light gas gun

    International Nuclear Information System (INIS)

    Small, light projectiles have been accelerated to high speeds using a two-stage light gas gun at Oak Ridge National Laboratory. With 35-mg plastic projectiles (4 mm in diameter), speeds of up to 4.5 km/s have been recorded. The ''pipe gun'' technique for freezing hydrogen isotopes in situ in the gun barrel has been used to accelerate deuterium pellets (nominal diameter of 4 mm) to velocities of up to 2.85 km/s. The primary application of this technology is for plasma fueling of fusion devices via pellet injection of hydrogen isotopes. Conventional pellet injectors are limited to pellet speeds in the range 1-2 km/s. Higher velocities are desirable for plasma fueling applications, and the two-stage pneumatic technique offers performance in a higher velocity regime. However, experimental results indicate that the use of sabots to encase the cryogenic pellets and protect them for the high peak pressures will be required to reliably attain intact pellets at speeds of ∼3 km/s or greater. In some limited tests, lithium hydride pellets were accelerated to speeds of up to 4.2 km/s. Also, repetitive operation of the two-stage gun (four plastic pellets fired at ∼0.5 Hz) was demonstrated for the first time in preliminary tests. The equipment and operation are described, and experimental results and some comparisons with a theoretical model are presented. 17 refs., 6 figs., 2 tabs

  12. Radiation hardness investigation of avalanche photodiodes for the Projectile Spectator Detector readout at the Compressed Baryonic Matter experiment

    International Nuclear Information System (INIS)

    In this paper, we discuss results of avalanche photodiodes radiation tests for Projectile Spectator Detector at future Compressed Baryonic Matter experiment. The tests were carried out in Nuclear Physics Institute of ASCR in Řež using the cyclotron facility. Secondary neutron beam was used for irradiation because the main radiation damage in the Projectile Spectator Detector is caused by neutrons. Two types of the avalanche photodiodes from Zecotek and Ketek manufacturers were investigated. Special attention was given to the noise investigation and self-annealing after the irradiation. We have irradiated two Ketek PM3375 diodes with equivalent dose for 1 MeV neutrons equal to 2.5±0.2×1012 n/cm2, and single Zecotek MAPD-3N diode with equivalent dose for 1 MeV neutrons equal to 3.4±0.2×1012 n/cm2. All the types of the diodes have shown an increasing level of the noise after the irradiation. From that we can conclude that those avalanche photodiodes are not able to detect single photons anymore due to high noise levels

  13. Atomic Physics with Accelerators: Projectile Electron Spectroscopy (APAPES)

    International Nuclear Information System (INIS)

    The new research initiative APAPES (http://apapes.physics.uoc.gr/) has already established a new experimental station with a beam line dedicated for atomic collisions physics research, at the 5 MV TANDEM accelerator of the National Research Centre ''Demokritos'' in Athens, Greece. A complete zero-degree Auger projectile spectroscopy (ZAPS) apparatus has been put together to perform high resolution studies of electrons emitted in ion-atom collisions. A single stage hemispherical spectrometer with a 2-dimensional Position Sensitive Detector (PSD) combined with a doubly-differentially pumped gas target will be used to perform a systematic isoelectronic investigation of K-Auger spectra emitted from collisions of preexcited and ground state He-like ions with gas targets using novel techniques. Our intention is to provide a more thorough understanding of cascade feeding of the 1s2s2p 4P metastable states produced by electron capture in collisions of He-like ions with gas targets and further elucidate their role in the non-statistical production of excited three-electron 1s2s2p states by electron capture, recently a field of conflicting interpretations awaiting further resolution. At the moment, the apparatus is being completed and the spectrometer will soon be fully operational. Here we present the project progress and the recent high resolution spectrum obtained in collisions of 12 MeV C4+ on a Neon gas target

  14. Study of Hypervelocity Projectile Impact on Thick Metal Plates

    Directory of Open Access Journals (Sweden)

    Shawoon K. Roy

    2016-01-01

    Full Text Available Hypervelocity impacts generate extreme pressure and shock waves in impacted targets that undergo severe localized deformation within a few microseconds. These impact experiments pose unique challenges in terms of obtaining accurate measurements. Similarly, simulating these experiments is not straightforward. This study proposed an approach to experimentally measure the velocity of the back surface of an A36 steel plate impacted by a projectile. All experiments used a combination of a two-stage light-gas gun and the photonic Doppler velocimetry (PDV technique. The experimental data were used to benchmark and verify computational studies. Two different finite-element methods were used to simulate the experiments: Lagrangian-based smooth particle hydrodynamics (SPH and Eulerian-based hydrocode. Both codes used the Johnson-Cook material model and the Mie-Grüneisen equation of state. Experiments and simulations were compared based on the physical damage area and the back surface velocity. The results of this study showed that the proposed simulation approaches could be used to reduce the need for expensive experiments.

  15. MEMIN Project: The Search for Suitable Projectile Material in Meso-Scale Hypervelocity Cratering Experiments

    Science.gov (United States)

    Domke, I.; Deutsch, A.; Hecht, L.; Kenkmann, T.

    2010-03-01

    We report textural and geochemical data (EMP, LA-ICP-MS) for different types of steel and the iron meteorites Arispe (IC) and Campo del Cielo (IAB) that are evaluated as projectile materials in hypervelocity cratering experiments .

  16. RESEARCH ON THE BASE CAVITY OF A SUB-LAUNCHED PROJECTILE

    Institute of Scientific and Technical Information of China (English)

    CAO Jia-yi; LU Chuan-jing; CHEN Ying; CHEN Xin; LI Jie

    2012-01-01

    The finite volume method based on a multiphase model is adopted to solve the Reynolds-Averaged Navier-Stokes (RANS)equations,which takes into account the effects of fluid compressibility,viscosity,gravity,medium mixture and energy transfer of water and combustion gas.The program Fluent User Define Function (UDF) module combined with the dynamic mesh method is employed to simulate the coupling flow field of combustion gas,water field and trajectory of projectile.The results show that the volume of gas cavity at the bottom of projectile and tail pressure will fluctuate after bottom of the projectile leaving the launch tube.The cause of the fluctuation is analyzed and its effects on the trajectory of projectile are presented.The numerical and experimental results agree well with each other.

  17. A New Simple Model for the Mushrooming Deformation of Projectile Impacting on A Deformable Target

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaoqing; Yang Guitong

    2004-01-01

    Based on Taylor's model and Hawkyard's model, a new simple model for the mushrooming deformation of projectile impacting on a deformable target is installed considering the penetration of the projectile to the deformable target. In the model, the following time-dependent variables are involved in: the extent and the particle velocity in the rigid zone; the extent, the cross-section area and the particle velocity in plastic zone; the velocity and depth of the penetrating of projectile to the target. Solving the set of equations, analytic solution is given. The profiles of deformed projectile and shape parameters for different initial impact velocities are shown. The duration time of deformation increases with increasing the impact velocity. The analytical results by using this model are coincident with experimental result.

  18. Development of odd-Z-projectile reactions for transactinide element synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Folden III, Charles Marvin

    2004-11-04

    The development of new odd-Z-projectile reactions leading to the production of transactinide elements is described. The cross section of the even-Z-projectile 208Pb(64Ni, n)271Ds reaction was measured at two new energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, seven decay chains attributable to 271Ds were observed. These data, combined with previous results, establish an excitation function for the production of 271Ds. The maximum cross section was 20 +15 -11 pb at a center-of-target energy of 311.5 MeV in the laboratory frame.The data from the 271Ds experiments were used to estimate the optimum beam energy for the new odd-Z-projectile 208Pb(65Cu, n)272-111 reaction using the Fusion by Diffusion theory proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski. A cross section for this reaction was measured for the first time, at a center-of-target energy of 321.1 MeV in the laboratory frame. The excitation energy f or compound nuclei formed at the target center was 13.2 MeV. One decay chain was observed, resulting in a measured cross section of 1.7 +3.9 -1.4 pb. This decay chain is in good agreement with previously published data on the decay of 272-111.The new odd-Z-projectile 208Pb(55Mn, n)262Bh reaction was studied at three different projectile energies, and 33 decay chains of 262Bh were observed. The existence of a previously reported alpha-decaying isomeric state in this nuclide was confirmed. Production of the ground state was preferred at all three beam energies. The maximum cross section was 540 +180 -150 pb at a projectile center-of-target energy of 264.0 MeV. This cross section is much larger than that previously reported for the even-Z-projectile 209Bi(54Cr, n)262Bh reaction, which may be because the 54Cr projectile energies in the latter reaction were too high for optimum production of the 1n product. At the highest projectile energy of 268.0 MeV in the target center, two decay

  19. Development of odd-Z-projectile reactions for transactinide element synthesis

    International Nuclear Information System (INIS)

    The development of new odd-Z-projectile reactions leading to the production of transactinide elements is described. The cross section of the even-Z-projectile 208Pb(64Ni, n)271Ds reaction was measured at two new energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, seven decay chains attributable to 271Ds were observed. These data, combined with previous results, establish an excitation function for the production of 271Ds. The maximum cross section was 20 +15 -11 pb at a center-of-target energy of 311.5 MeV in the laboratory frame.The data from the 271Ds experiments were used to estimate the optimum beam energy for the new odd-Z-projectile 208Pb(65Cu, n)272-111 reaction using the Fusion by Diffusion theory proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski. A cross section for this reaction was measured for the first time, at a center-of-target energy of 321.1 MeV in the laboratory frame. The excitation energy f or compound nuclei formed at the target center was 13.2 MeV. One decay chain was observed, resulting in a measured cross section of 1.7 +3.9 -1.4 pb. This decay chain is in good agreement with previously published data on the decay of 272-111.The new odd-Z-projectile 208Pb(55Mn, n)262Bh reaction was studied at three different projectile energies, and 33 decay chains of 262Bh were observed. The existence of a previously reported alpha-decaying isomeric state in this nuclide was confirmed. Production of the ground state was preferred at all three beam energies. The maximum cross section was 540 +180 -150 pb at a projectile center-of-target energy of 264.0 MeV. This cross section is much larger than that previously reported for the even-Z-projectile 209Bi(54Cr, n)262Bh reaction, which may be because the 54Cr projectile energies in the latter reaction were too high for optimum production of the 1n product. At the highest projectile energy of 268.0 MeV in the target center, two decay

  20. Histologic Analysis of Pig Muscle Tissue after Wounding with a High-Velocity Projectile - Preliminary Report

    OpenAIRE

    Korać, Želimir; Crnica, Suad; Demarin, Vida

    2006-01-01

    Terminal ballistics of high-velocity projectiles is focused primarily on evaluation of the effects of penetrating projectiles on tissue simulants, but there is always a question of their similarity with live tissue. Ethical problems related to using live animals in terminal ballistic researches have resulted in a reduced number of these experiments. The aim of this study was to analyze histologic effects of high-velocity missiles in swine muscle tissue. The hypothesis was that a penetrating p...

  1. Projectile fragmentation of 500 A MeV {sup 56}Fe in nuclear emulsion

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jun-Sheng, E-mail: lijs@dns.sxnu.edu.cn [Institute of Modern Physics, Shanxi Normal University, Linfen 041004 (China); Zhang, Dong-Hai; Li, Hui-Ling [Institute of Modern Physics, Shanxi Normal University, Linfen 041004 (China); Yasuda, N. [Fundamental Technology Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2013-07-15

    N-4 stacks of nuclear emulsion were exposed to 500 A MeV {sup 56}Fe ions at the HIMAC NIRS. Particle production was investigated in {sup 56}Fe–Em interactions. The multiplicity distribution of projectile fragments was done in this paper and compared with interactions induced by {sup 56}Fe and other heavy ions in nuclear emulsion at other energies. The variation of characteristics of the heavy ion interactions with the mass and energy of the projectile is studied.

  2. Probable Projectile-Target Combinations for the Synthesis of Super Heavy Nucleus 286112

    OpenAIRE

    Santhosh, K. P.; V. Bobby Jose

    2014-01-01

    The fusion cross sections for the reactions of all the projectile-target combinations found in the cold valleys of 286112 have been studied using scattering potential as the sum of Coulomb and proximity potential, so as to predict the most probable projectile-target combinations in heavy ion fusion reactions for the synthesis of super heavy nucleus 286112. While considering the nature of potential pockets and half lives of the colliding nuclei, the systems 82Ge + 204Hg, 80...

  3. Probable projectile-target combinations for the synthesis of super heavy nucleus $^{286}$112

    OpenAIRE

    Santhosh, K. P.; Jose, V. Bobby

    2014-01-01

    The fusion cross sections for the reactions of all the projectile-target combinations found in the cold valleys of $^{286}$112 have been studied using scattering potential as the sum of Coulomb and proximity potential, so as to predict the most probable projectile-target combinations in heavy ion fusion reactions for the synthesis of super heavy nucleus $^{286}$112. While considering the nature of potential pockets and half lives of the colliding nuclei, the systems $^{82}$Ge + $^{204}$Hg, $^...

  4. Finite Element Modeling of Transient Temperatures in a Small-Caliber Projectile

    OpenAIRE

    M. B. Thomas; Leon Dozier

    2010-01-01

    Problem statement: Future generations of intelligent munitions will use Microelectromechanical Systems (MEMS) for guidance, fuzing logic and assessment of the battlefield environment. The temperatures fund in a gun system, however, are sufficient to damage some materials used in the fabrication of MEMS. The motivation of this study is to model the dynamic temperature distribution in a typical small-caliber projectile. Approach: An axisymmetric finite-element model of a projectile is developed...

  5. Perforation of thin aluminum alloy plates by blunt projectiles: An experimental and numerical investigation

    International Nuclear Information System (INIS)

    Reducing the armor weight has become a research focus in terms of armored material. Due to high strength-to-density ratio, aluminum alloy has become a potential light armored material. In this study, both lab-scale ballistic test and finite element simulation were adopted to examine the ballistic resistance of aluminum alloy targets. Blunt high strength steel projectiles with 12.7 mm diameter were launched by light gas gun against 3.3 mm thickness 7A04 aluminum alloy plates at a velocity of 90∼170 m/s. The ballistic limit velocity was obtained. Plugging failure and obvious structure deformation of targets were observed. Corresponding 2D finite element simulations were conducted by ABAQUS/EXPLICIT combined with material performance testing. The validity of numerical simulations was verified by comparing with the experimental results. Detailed analysis of the failure modes and characters of the targets were carried out to reveal the target damage mechanism combined with the numerical simulation.

  6. Fairly direct hit. Advances in imaging of shotgun projectiles in MRI

    Energy Technology Data Exchange (ETDEWEB)

    Eggert, Sebastian [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); University of Zurich, Institute of Forensic Medicine, Zurich (Switzerland); Kubik-Huch, Rahel A.; Peters, Alexander [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); Klarhoefer, Markus [Siemens Healthcare, Zurich (Switzerland); Bolliger, Stephan A.; Thali, Michael J. [University of Zurich, Institute of Forensic Medicine, Zurich (Switzerland); Anderson, Suzanne [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); University of Notre Dame Australia, Radiology, Sydney School of Medicine, Sydney, NSW (Australia); Froehlich, Johannes M. [Federal Institute of Technology, Pharmaceutical Sciences, Zurich (Switzerland)

    2015-09-15

    To investigate the magnetic properties of different types of projectiles and qualify the metal artefact reduction technique for diagnostic and/or forensic MRI. Ten different projectiles embedded in ordnance gelatine blocks underwent an in vitro 1.5-T MR study with seven sequences including a recently developed metal artefact reduction sequence (Advanced WARP) combining VAT (view-angle-tilting) and SEMAC (slice-encoding metal-artefact-correction). Resulting image quality (five-point scale: 1=best; 5=worst) was scored. Quantifiable magnetic characteristics were correlated with qualitative rating of the MR sequences and torque dislodgment. Metal artefact reduction sequence (median: 2.5) significantly (p < 0.001) improves depiction of projectiles in comparison to all other MR pulse sequences (median: 4.75). Images from diamagnetic composed bullets (median: 2) are much less disturbed compared to magnetic attracted ones (median: 5). Correlation (0.623) between deflection angle measurement (ferromagnetic mean 84.2 ; paramagnetic 62 ; diamagnetic mean 0 ) and median qualitative image quality was highly significant (p = 0.027). Torque dislodgement was distinct for elongated magnetic attracted projectiles. Significant improvement of MR imaging of projectiles using metal artefact reduction techniques has important implications for diagnostic/forensic work-up. The correlations between magnetic attraction force, deflection-angle results and image properties demonstrate that the MR safety of projectiles can be estimated with one of these methods. (orig.)

  7. Fairly direct hit. Advances in imaging of shotgun projectiles in MRI

    International Nuclear Information System (INIS)

    To investigate the magnetic properties of different types of projectiles and qualify the metal artefact reduction technique for diagnostic and/or forensic MRI. Ten different projectiles embedded in ordnance gelatine blocks underwent an in vitro 1.5-T MR study with seven sequences including a recently developed metal artefact reduction sequence (Advanced WARP) combining VAT (view-angle-tilting) and SEMAC (slice-encoding metal-artefact-correction). Resulting image quality (five-point scale: 1=best; 5=worst) was scored. Quantifiable magnetic characteristics were correlated with qualitative rating of the MR sequences and torque dislodgment. Metal artefact reduction sequence (median: 2.5) significantly (p < 0.001) improves depiction of projectiles in comparison to all other MR pulse sequences (median: 4.75). Images from diamagnetic composed bullets (median: 2) are much less disturbed compared to magnetic attracted ones (median: 5). Correlation (0.623) between deflection angle measurement (ferromagnetic mean 84.2 ; paramagnetic 62 ; diamagnetic mean 0 ) and median qualitative image quality was highly significant (p = 0.027). Torque dislodgement was distinct for elongated magnetic attracted projectiles. Significant improvement of MR imaging of projectiles using metal artefact reduction techniques has important implications for diagnostic/forensic work-up. The correlations between magnetic attraction force, deflection-angle results and image properties demonstrate that the MR safety of projectiles can be estimated with one of these methods. (orig.)

  8. Fragmentation of armor piercing steel projectiles upon oblique perforation of steel plates

    Science.gov (United States)

    Paris, V.; Weiss, A.; Vizel, A.; Ran, E.; Aizik, F.

    2012-08-01

    In this study, a constitutive strength and failure model for a steel core of a14.5 mm API projectile was developed. Dynamic response of a projectile steel core was described by the Johnson-Cook constitutive model combined with principal tensile stress spall model. In order to obtain the parameters required for numerical description of projectile core material behavior, a series of planar impact experiments was done. The parameters of the Johnson-Cook constitutive model were extracted by matching simulated and experimental velocity profiles of planar impact. A series of oblique ballistic experiments with x-ray monitoring was carried out to study the effect of obliquity angle and armor steel plate thickness on shattering behavior of the 14.5 mm API projectile. According to analysis of x-ray images the fragmentation level increases with both steel plate thickness and angle of inclination. The numerical modeling of the ballistic experiments was done using commercial finite element code, LS-DYNA. Dynamic response of high hardness (HH) armor steel was described using a modified Johnson-Cook strength and failure model. A series of simulations with various values of maximal principal tensile stress was run in order to capture the overall fracture behavior of the projectile's core. Reasonable agreement between simulated and x-ray failure pattern of projectile core has been observed.

  9. Locus Model for the Pellet's Shiver of Smoke Projectile%烟幕弹的发烟剂碎块轨迹模型

    Institute of Scientific and Technical Information of China (English)

    朱晨光; 潘功配; 陈敬业; 杨志强

    2006-01-01

    利用飞散物在运动过程中所受到的空气阻力和重力建立飞散物运动方程,用高速摄影仪拍摄了烟幕爆炸成烟过程,并用实验结果求出了相关系数,校正了模型.结果发现空气阻力对烟幕成型有明显的影响.%The locus equation for the pellet's shiver of smoke projectile was established by using the air friction and the gravitation, and the solving process of equation was presented. The exploding process of smoke projectile was shot by a high speed camera. Test data were used to obtain related coefficients, and the mathematical model was modified further.The results illustrate that air friction effect on the flying locus of shiver is significant.

  10. Behavior of steel fiber high strength concrete under impact of projectiles

    Directory of Open Access Journals (Sweden)

    Cánovas, M. F.

    2012-09-01

    Full Text Available This paper presents the results of the investigation carried out by the authors about the behavior of 80 MPa characteristic compression strength concrete reinforced with different amount of high carbon content steel fiber, submit to impact of different caliber projectiles, determining the thickness of this type of concrete walls needs to prevent no perforation, as well as the maximum penetration to reach into them, so that in the event of no perforation and only penetration, "scabbing" phenomena does not take place on the rear surface of the wall. Prior to ballistic testing was necessary to design the high-strength concrete with specific mechanical properties, especially those related to ductility, since these special concrete must absorb the high energy of projectiles and also the shock waves that accompany them.Este trabajo presenta los resultados de la investigación llevada a cabo por los autores sobre el comportamiento de hormigón de 80 MPa de resistencia característica a compresión reforzado con diferentes cuantías de fibras de acero de alto contenido en carbono sometido al impacto de proyectiles de distintos calibres, determinando el espesor de muros de este tipo de hormigón que sería preciso disponer para impedir su perforación por dichos proyectiles, así como los valores máximos de penetración, para que en el caso de no producirse perforación y sólo penetración, no se genera cráter, “scabbing”, en el trasdós de los mismos. Previamente a los ensayos balísticos fue preciso diseñar los hormigones para que, presentaran determinadas características mecánicas, especialmente las relacionadas con la ductilidad, dado que estos hormigones especiales deben absorber la elevada energía que le transmiten los proyectiles y las ondas de choque que los acompañan.

  11. Observation of wounding characteristics in dogs wounded by super velocity projectile

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To understand wounding characteristics in dogs woundedby super velocity projectile with a purpose of providing a basis for prevention and treatment of such wounds.Methods: A specially-made explosive gun was used to shoot aluminium bullet weighing 3.0 g and 1.4 g to injure both legs of dogs at velocities of 2 330 m/s, 3 200 m/s and 4 250 m/s, respectively, and the soap specially made was also shot. At the same time, steel ball of 1.03 g was shot with a Type 53 smooth chamber gun at a speed of 1 280 m/s. Within 30 min after wounding, debridement and pathological anatomy were performed and specimens were taken for light microscope observation.Results: When the dogs were wounded by the 3 g bullet at speed of 2 330 m/s, the entrance of the left leg was penetrated explosively with a defect area of 225 cm2, and the femur trunk was also injured and the residual femur had comminution fracture. The exit of the right leg was blindly wounded with a defect area of 63 cm2, but only the skin was not penetrated. Both testes and part pelvis were injured too. Under light microscope, degenerative myofibers and bleeding of the spatium between the myofibers could be found at the place 4 cm away from the wounding track. Furthermore, serious bleeding of the bladder and blood vessels of the brain could be observed. The lungs showed changes of blast injury. Vacuolar change was presented in the cytoplasm of hepatocytes. Injuries of the animals in other two experimental groups were similar to those described above, but the defect area of the wounded track was 124 cm2 in the group of 4 250 m/s. Injuries caused by the steel ball were milder than caused by the explosive gun. The volume of the residual cavity in the soap was 5 000 ml.Conclusions: The super-velocity projectile causes destructive damage to the local tissues and multi-organ injuries. Therefore, the practical medical care needs not only amputation but also management of multi-organ injuries.

  12. Production and transport of the excited states of projectile ions in ion-solid interaction; Production et transport des etats excites du projectile en interaction ion-solide

    Energy Technology Data Exchange (ETDEWEB)

    Lamour, E

    1997-11-01

    In ion-solid collisions, more excited states of projectile ions with high angular momenta l are populated than in ion-atom collisions. The use of 13.6 MeV/u Ar{sup 18+} projectile ions and solid carbon targets allowed us to study Ar{sup 17+} excited states initially populated by electron capture. Using various targets with increasing thickness from 3.5 to 200 {mu}g/cm{sup 2}, the evolution of excited states from the single collision condition to the population equilibrium was investigated. We observed the evolution of the Lyman line intensities as a function of the ion transit time inside the target (sensitive to core state population) and as a function of the ion time of flight behind the target (sensitive to Rydberg state population). To explain the experimental results, a complete theoretical analysis of the transport of excited states inside the medium was performed. We used two different collisional models. The first one is a rate equation model based on a statistical description of binary collisions of the projectile with target atoms. The second one is a classical transport theory based on an equation describing the motion of the projectile electron on a classical orbit perturbed by a stochastic force. A comparison with experiment shows that such a collisional approach allows to interpret the excited l-state population, but fails in describing the core state population. The observed l mixing in these states is much larger than predicted by the models. The polarization of the medium induced by the projectile ion, with both models do not take into account, could be responsible for this mixing by means of the Stark effect. (author)

  13. Progress in spheromaks for power amplification and transfer to hypervelocity projectiles

    International Nuclear Information System (INIS)

    The goal of the spheromak program at Los Alamos is to develop a new scheme to accelerate material objects to hypervelocities (velocities above a few kilometers per second). This capability would provide a valuable tool to other research programs, such as weapons lethality tests, studies of the properties of materials at extremely high pressures, and magnetically-insulated impact fusion. In the authors' scheme, the magnetized spheromak plasma, confined by a metallic wall, would act as an energy storage and transfer medium. As high explosives (HE) compress part of the metallic wall against the spheromak magnetic field, the spheromak stores energy. Once the spheromak reaches a critical dimension, the MHD equilibrium is expected to switch (much faster than the compression time) to a new configuration, which is the minimum-energy state of the new geometry. This witching action would result in the spheromak magnetic field imparting a sudden, strong pressure to a small section of the wall, which would then break away as an accelerated projectile. The scheme, including the basis for the spheromak switching effect, are described

  14. Hypervelocity impact of rod projectiles with L/D from 1 to 32

    International Nuclear Information System (INIS)

    Beside a short remark on the ''hydrodynamic theory of rod projectiles'', the paper deals with the terminal ballistic behaviour of cylindrical projectiles against semi-infinite targets. Experimental data of EMI, completed by results of some other authors, are presented. Crater parameters like depth, diameter and volume and their dependence on projectile velocity (up to 5000 m/s), projectile and target material properties, as well as L/D-ratios (1 - 32), are discussed. Mainly the projectile materials steel and tungsten sinter-alloys are considered. Target materials are mild steel and high strength steel, an Al-alloy and a tungsten sinter-alloy. The results show that the influence of material density on the crater dimensions is considerably greater than the influence of strength. The L/D ratio determines the velocity dependence of crater depth, diameter and volume. At high velocities in the hydrodynamic regime, the crater depth of short cylinders (L/D -- 1) is approximately proportional to v/sub p//sup 2/3/ (v/sub p/ = projectile velocity). With increasing L/D-ratio, the slope of the penetration curves decreases and converges for rods (L/D >> 1) versus a saturation, i.e. becomes nearly independent on v/sub p/. A consequence of this saturation is the existence of a so-called ''tangent velocity'', above which an optimal increase of efficiency is only realized by increasing the projectile mass and not the velocity. Furthermore, ballistic limits of real targets like single plates and symmetric double plates meteorite bumper shield) are taken into account. The expected better performance of ''segmented rods'' is also discussed

  15. Target-projectile interaction during impact melting at Kamil Crater, Egypt

    Science.gov (United States)

    Fazio, Agnese; D'Orazio, Massimo; Cordier, Carole; Folco, Luigi

    2016-05-01

    In small meteorite impacts, the projectile may survive through fragmentation; in addition, it may melt, and chemically and physically interact with both shocked and melted target rocks. However, the mixing/mingling between projectile and target melts is a process still not completely understood. Kamil Crater (45 m in diameter; Egypt), generated by the hypervelocity impact of the Gebel Kamil Ni-rich ataxite on sandstone target, allows to study the target-projectile interaction in a simple and fresh geological setting. We conducted a petrographic and geochemical study of macroscopic impact melt lapilli and bombs ejected from the crater, which were collected during our geophysical campaign in February 2010. Two types of glasses constitute the impact melt lapilli and bombs: a white glass and a dark glass. The white glass is mostly made of SiO2 and it is devoid of inclusions. Its negligible Ni and Co contents suggest derivation from the target rocks without interaction with the projectile (compression stage and the excavation stage, projectile and target liquids formed at their interface and chemically interact in a restricted zone. Projectile contamination affected only a shallow portion of the target rocks. The SiO2 melt that eventually solidified as white glass behaved as an immiscible liquid and did not interact with the projectile. During the excavation stage dark glass melt engulfed and coated the white glass melt, target fragments, and got stuck to iron meteorite shrapnel fragments. This model could also explain the common formation of white and dark glasses in small impact craters generated by iron bodies (e.g., Wabar).

  16. Characteristics study of projectiles lightest fragment for 84Kr36 - emulsion interaction at around 1 A GeV

    CERN Document Server

    Marimuthu, N; Inbanathan, S S R

    2016-01-01

    The present article significantly investigated projectiles lightest fragments (proton) multiplicity distribution and probability distribution with 84Kr36 emulsion collision at around 1 A GeV. The multiplicity and normalized multiplicity of projectiles lightest fragments (proton) is correlated with the compound particles, shower particles, black particles, grey particles, helium fragments particles and heavily ionizing charged particles. It is found that projectiles lightest fragments (proton) are strongly correlated with compound particles and shower particles rather than other particles and the average multiplicity of projectiles lightest fragments (proton) increases with increasing compound, shower and heavy ionizing particles. Normalized projectiles lightest fragments (proton) are strongly correlated with compound particles, shower particles and heavy ionizing charge particles. The multiplicity distribution of the projectiles lightest fragments (proton) emitted in the 84Kr36 + emulsion interaction at aroun...

  17. The African Origin of Complex Projectile Technology: An Analysis Using Tip Cross-Sectional Area and Perimeter

    OpenAIRE

    Shea, John J.; Matthew L. Sisk

    2011-01-01

    Despite a body of literature focusing on the functionality of modern and stylistically distinct projectile points, comparatively little attention has been paid to quantifying the functionality of the early stages of projectile use. Previous work identified a simple ballistics measure, the Tip Cross-Sectional Area, as a way of determining if a given class of stone points could have served as effective projectile armatures. Here we use this in combination with an alternate measure, the Tip Cros...

  18. Characteristics study of projectiles lightest fragment for 84Kr36 - emulsion interaction at around 1 A GeV

    OpenAIRE

    Marimuthu, N.; Singh, V; Inbanathan, S. S. R.

    2016-01-01

    The present article significantly investigated projectiles lightest fragments (proton) multiplicity distribution and probability distribution with 84Kr36 emulsion collision at around 1 A GeV. The multiplicity and normalized multiplicity of projectiles lightest fragments (proton) is correlated with the compound particles, shower particles, black particles, grey particles, helium fragments particles and heavily ionizing charged particles. It is found that projectiles lightest fragments (proton)...

  19. Chemical projectile-target interaction during hypervelocity cratering experiments (MEMIN project).

    Science.gov (United States)

    Ebert, M.; Hecht, L.; Deutsch, A.; Kenkmann, T.

    2012-04-01

    The detection and identification of meteoritic components in impact-derived rocks are of great value for confirming an impact origin and reconstructing the type of extraterrestrial material that repeatedly stroke the Earth during geologic evolution [1]. However, little is known about processes that control the projectile distribution into the various impactites that originate during the cratering and excavation process, and inter-element fractionation between siderophile elements during impact cratering. In the context of the MEMIN project, cratering experiments have been performed using spheres of Cr-V-Co-Mo-W-rich steel and of the iron meteorite Campo del Cielo (IAB) as projectiles accelerated to about 5 km/s, and blocks of Seeberger sandstone as target. The experiments were carried out at the two-stage acceleration facilities of the Fraunhofer Ernst-Mach-Institute (Freiburg). Our results are based on geochemical analyses of highly shocked ejecta material. The ejecta show various shock features including multiple sets of planar deformations features (PDF) in quartz, diaplectic quartz, and partial melting of the sandstone. Melting is concentrated in the phyllosilicate-bearing sandstone matrix but involves quartz, too. Droplets of molten projectile have entered the low-viscosity sandstone melt but not quartz glass. Silica-rich sandstone melts are enriched in the elements that are used to trace the projectile, like Fe, Ni, Cr, Co, and V (but no or little W and Mo). Inter-element ratios of these "projectile" tracer elements within the contaminated sandstone melt may be strongly modified from the original ratios in the projectiles. This fractionation most likely result from variation in the lithophile or siderophile character and/or from differences in reactivity of these tracer elements with oxygen [2] during interaction of metal melt with silicate melt. The shocked quartz with PDF is also enriched in Fe and Ni (experiment with a meteorite iron projectile) and in Fe

  20. Numerical Investigation of Bending-Body Projectile Aerodynamics for Maneuver Control

    Science.gov (United States)

    Youn, Eric; Silton, Sidra

    2015-11-01

    Precision munitions are an active area of research for the U.S. Army. Canard-control actuators have historically been the primary mechanism used to maneuver fin-stabilized, gun-launched munitions. Canards are small, fin-like control surfaces mounted at the forward section of the munition to provide the pitching moment necessary to rotate the body in the freestream flow. The additional lift force due to the rotated body and the canards then alters the flight path toward the intended target. As velocity and maneuverability requirements continue to increase, investigation of other maneuver mechanisms becomes necessary. One option for a projectile with a large length-to-diameter ratio (L/D) is a bending-body design, which imparts a curvature to the projectile body along its axis. This investigation uses full Navier-Stokes computational fluid dynamics simulations to evaluate the effectiveness of an 8-degree bent nose tip on an 8-degree bent forward section of an L/D =10 projectile. The aerodynamic control effectiveness of the bending-body concept is compared to that of a standard L/D =10 straight-body projectile as well as that of the same projectile with traditional canards. All simulations were performed at supersonic velocities between Mach 2-4.

  1. CO2 Cluster Ion Beam, an Alternative Projectile for Secondary Ion Mass Spectrometry

    Science.gov (United States)

    Tian, Hua; Maciążek, Dawid; Postawa, Zbigniew; Garrison, Barbara J.; Winograd, Nicholas

    2016-09-01

    The emergence of argon-based gas cluster ion beams for SIMS experiments opens new possibilities for molecular depth profiling and 3D chemical imaging. These beams generally leave less surface chemical damage and yield mass spectra with reduced fragmentation compared with smaller cluster projectiles. For nanoscale bioimaging applications, however, limited sensitivity due to low ionization probability and technical challenges of beam focusing remain problematic. The use of gas cluster ion beams based upon systems other than argon offer an opportunity to resolve these difficulties. Here we report on the prospects of employing CO2 as a simple alternative to argon. Ionization efficiency, chemical damage, sputter rate, and beam focus are investigated on model compounds using a series of CO2 and Ar cluster projectiles (cluster size 1000-5000) with the same mass. The results show that the two projectiles are very similar in each of these aspects. Computer simulations comparing the impact of Ar2000 and (CO2)2000 on an organic target also confirm that the CO2 molecules in the cluster projectile remain intact, acting as a single particle of m/z 44. The imaging resolution employing CO2 cluster projectiles is improved by more than a factor of two. The advantage of CO2 versus Ar is also related to the increased stability which, in addition, facilitates the operation of the gas cluster ion beams (GCIB) system at lower backing pressure.

  2. EXPERIMENTAL AND THEORETICAL STUDY ON THE HIGH-SPEED HORIZONTAL WATER ENTRY BEHAVIORS OF CYLINDRICAL PROJECTILES

    Institute of Scientific and Technical Information of China (English)

    GUO Zi-tao; ZHANG Wei; WANG Cong

    2012-01-01

    In this article,the horizontal water-entry of flat-nose projectiles of two different lengths at impact velocities of 400 r/s-600 m/s is studied experimentally and theoretically.Based on the solution of the Rayleigh-Besant problem,a set of projectile dynamic equations are derived and a cavity model is built to describe the projectile's water entry dynamics.A parameter in the cavity model is determined by employing the principle of energy conservation.The results indicate that the flat-nose projectiles enjoy a good stability of trajectory,the drag coefficient and the velocity decay coefficient are dependent on the cavitation number,and increase along the penetration distance but with a relatively small variation.The maximum cavity radius decreases monotonically with the penetration distance.Projectiles with the same nose shapes at different initial velocities have a basically consistent cavity dimension before the deep pinching off phenomenon occurs.Good agreements are observed between results obtained by the analytical model and the experimental results.

  3. Normal and Oblique Impacts of Hard Projectile on Single and Layered Plates-An Experimental Study

    Directory of Open Access Journals (Sweden)

    V. Madhu

    2003-04-01

    Full Text Available The phenomenon of ordnance velocity impact of projectile on single and layered plates is of interest for many applications. In this paper. an experimental study of normal and oblique impacts or an ogive shaped, hard steel projectile on single and layered plates of mild steel and aluminium is presented. The projectiles were fired at an impact velocity of about 820 ms-1. The plate thickness was varied in the range 10 mm to 40 mm and the ratio of plate thickness to the diameter of the projectile varied in the range 1.5 to 13.0. Observations on target damage and measurements of incident and residual velocities for different angles of impact are presented. Plate thickness t*, for which the incident velocity is the ballistic limit, is determined. Computer simulations were carried out using a hydrodynamic code to simulate the normal impact of a projectile and compared these with the experimental results. Experiments were performed to evaluate the response of these plates of intermediate thickness when layered. and the results were compared to the results of single plate of same total thickness.

  4. Light-ion elastic scattering potentials: Energy and projectile-mass dependence

    International Nuclear Information System (INIS)

    Volume integrals of the real potentials derived from elastic scattering studies of deuterons, tritons, 3He, and α particles have been calculated for data available from the lowest to the highest energy. These volume integrals have been plotted as a function of energy per nucleon for each projectile. By selecting energy regions where there were least ambiguities in the potentials and averaging the volume integrals in 1 MeV bins, the energy dependences were determined. The volume integrals show a logarithmic dependence on the energy per nucleon. The zero crossing of the potentials is at about the same value of ∼650 MeV/nucleon for all projectiles. With increasing projectile mass, the potentials become weaker, possibly due to Pauli blocking effects in the projectile. Neutron-rich projectiles have smaller volume integrals due to the manifestation of the isospin effect. A similar analysis of the imaginary volume integrals shows that they increase from zero at the lowest energies to about 100-150 MeV fm3 around 10 MeV/nucleon and then remain essentially constant

  5. CO2 Cluster Ion Beam, an Alternative Projectile for Secondary Ion Mass Spectrometry

    Science.gov (United States)

    Tian, Hua; Maciążek, Dawid; Postawa, Zbigniew; Garrison, Barbara J.; Winograd, Nicholas

    2016-06-01

    The emergence of argon-based gas cluster ion beams for SIMS experiments opens new possibilities for molecular depth profiling and 3D chemical imaging. These beams generally leave less surface chemical damage and yield mass spectra with reduced fragmentation compared with smaller cluster projectiles. For nanoscale bioimaging applications, however, limited sensitivity due to low ionization probability and technical challenges of beam focusing remain problematic. The use of gas cluster ion beams based upon systems other than argon offer an opportunity to resolve these difficulties. Here we report on the prospects of employing CO2 as a simple alternative to argon. Ionization efficiency, chemical damage, sputter rate, and beam focus are investigated on model compounds using a series of CO2 and Ar cluster projectiles (cluster size 1000-5000) with the same mass. The results show that the two projectiles are very similar in each of these aspects. Computer simulations comparing the impact of Ar2000 and (CO2)2000 on an organic target also confirm that the CO2 molecules in the cluster projectile remain intact, acting as a single particle of m/z 44. The imaging resolution employing CO2 cluster projectiles is improved by more than a factor of two. The advantage of CO2 versus Ar is also related to the increased stability which, in addition, facilitates the operation of the gas cluster ion beams (GCIB) system at lower backing pressure.

  6. On the universal scaling in the electronic stopping cross section for heavy ion projectiles

    Science.gov (United States)

    Cabrera-Trujillo, R.; Martínez-Flores, C.; Trujillo-López, L. N.; Serkovic-Loli, L. N.

    2016-02-01

    Energy deposition of heavy ions when penetrating a material is of crucial importance in determining the damage to materials with implications in areas such as material science, plasma physics, radiotherapy and dosimetry. Due to the N-body electron problem, it has been thought that the electronic stopping cross section is unique for a given projectile-target combination and differs from system to system. In this work, we show that within the Bethe theory, there is a universal scaling when the electronic stopping cross sections and projectile kinetic energy are scaled properly in terms of the target mean excitation energy, ?, for all projectile-target combinations. We show that the scaling is given by ? as a function of ?, thus showing the importance of the characterization of the mean excitation energy. The scaling law expresses a systematic and universal behavior among complex projectile-target systems in the energy deposition, characterized by the minimum momentum transfer during the slowing down process. We provide an analytic expression for the universal scaling law for the stopping cross section of any projectile-target combination valid at high collision energies. Finally, we verify the universal scaling law by comparison to atomic and molecular experimental data available in the literature. We expect our findings will motivate further experimental work to verify our universal scaling for more complex systems in the absence of experimental data.

  7. Hydrocode Simulation with Modified Johnson-Cook Model and Experimental Analysis of Explosively Formed Projectiles

    Science.gov (United States)

    Hussain, G.; Hameed, A.; Hetherington, J. G.; Barton, P. C.; Malik, A. Q.

    2013-04-01

    The formation of mild steel (MS) and copper (Cu) explosively formed projectiles (EFPs) was simulated in AUTODYN using both the Johnson-Cook (JC) and modified Johnson-Cook (JCM) constitutive models. The JC model was modified by increasing the hardening constant by 10%. The previously established semi-empirical equations for diameter, length, velocity, and depth of penetration were used to verify the design of the EFP. The length-to-diameter (L/D) ratio of the warhead used in the simulation varied between 1 < L/D < 2. To avoid projectile distortion or breakup for large standoff applications, the design of the EFP warhead was modified to obtain a lower L/D ratio. Simulations from the JC model underestimated the EFP diameter, resulting in an unrealistically elongated projectile. This shortcoming was resolved by employing the JCM model, giving good agreement with the experimental results. The projectile velocity and hole characteristics in 10-mm-thick aluminum target plates were studied for both models. The semi-empirical equations and the JC model overestimated the projectile velocity, whereas the JCM model underestimated the velocity slightly when compared to the experimental results. The depths of penetration calculated by the semi-empirical equations in the aluminum (Al) target plate were 55 and 52 mm for Cu and MS EFPs, respectively.

  8. Fragmentation of armor piercing steel projectiles upon oblique perforation of steel plates

    Directory of Open Access Journals (Sweden)

    Aizik F.

    2012-08-01

    Full Text Available In this study, a constitutive strength and failure model for a steel core of a14.5 mm API projectile was developed. Dynamic response of a projectile steel core was described by the Johnson-Cook constitutive model combined with principal tensile stress spall model. In order to obtain the parameters required for numerical description of projectile core material behavior, a series of planar impact experiments was done. The parameters of the Johnson-Cook constitutive model were extracted by matching simulated and experimental velocity profiles of planar impact. A series of oblique ballistic experiments with x-ray monitoring was carried out to study the effect of obliquity angle and armor steel plate thickness on shattering behavior of the 14.5 mm API projectile. According to analysis of x-ray images the fragmentation level increases with both steel plate thickness and angle of inclination. The numerical modeling of the ballistic experiments was done using commercial finite element code, LS-DYNA. Dynamic response of high hardness (HH armor steel was described using a modified Johnson-Cook strength and failure model. A series of simulations with various values of maximal principal tensile stress was run in order to capture the overall fracture behavior of the projectile’s core. Reasonable agreement between simulated and x-ray failure pattern of projectile core has been observed.

  9. Light particle emission and projectile breakup in 35A MeV 12C induced collisions

    International Nuclear Information System (INIS)

    Inclusive spectra of p, d, t, 3He from 35A MeV 12C + C, Al, Cu, Au reactions as wll as coincidences between projectile-like fragments and light particles have been measured. The apparent temperature does not seem to depend on the size of the coincident fragment. An independent way to determine source velocities indicates that high energy protons are emitted from a source with a velocity close to half the beam velocity even in assymmetric reactions. We observed in in-plane enhancement in the azimuthal angular distributions of coincident projectile-like fragments which gets stronger with increasing mass of the triggering particle or the fragment. A discussion around momentum conservation effects shows that p * B correlations may originate form a combination of pure projectile breakup- and nucleon-nucleon quasi-elastic scattering process. The correlations observed in less peripheral collision need the introduction of a second, light particle emitting source

  10. Screening and antiscreening by projectile electrons in high-velocity atomic collisions

    International Nuclear Information System (INIS)

    The scattering amplitude for a projectile of nuclear charge Z1 carrying N electrons colliding with an atomic target with charge Z2, evaluated in the first Born approximation using hydrogenic wave functions, is compared with recent experimental results. In the present approximation where the minimum momentum transfer t/sub min/ is considered to be approximately independent of the final state of the projectile, the differential cross sections separate into a product of one term that depends only on the target times the square Z21(t) of an effective projectile charge. Here an analytic expression for Z21(t) is given for 2, 1, and 0 electrons. Some total ionization cross-section ratios are also given

  11. Determination of initial conditions of projectile fragmentation from transport model calculations

    International Nuclear Information System (INIS)

    Projectile fragmentation is a practical tool for producing radioactive ion beams in the laboratory and remains a very active field of research both experimentally and theoretically. In recent years we proposed a model for projectile fragmentation which could successfully explain different experimental observables. In initial stage of the reaction, depending upon the impact parameter projectile like fragments (PLF) of different masses are produced and its excitation is often characterized by a temperature at freeze-out condition. The main limitations of this model are (i) PLF size is calculated from straightline geometry and (ii) temperature profile is parameterized with the help of experimental data. In this work we have determined the PLF mass and its excitation directly from transport model based on Boltzmann-Uehling-Uhlenbeck (BUU) calculation

  12. Extended Range of a Gun Launched Smart Projectile Using Controllable Canards

    Directory of Open Access Journals (Sweden)

    Mark Costello

    2001-01-01

    Full Text Available This effort investigates the extent to which moveable canards can extend the range of indirect fire munitions using both projectile body and canard lift. Implications on terminal velocity and time of flight using this mechanism to extend range are examined for various canard configurations. Performance predictions are conducted using a six-degree-of-freedom simulation model that has previously been validated against range data. The projectile dynamic equations are formed in the body frame and aerodynamic loads from the body and canards are Mach number and angle of attack dependent. The projectile body aerodynamic moments include unsteady aerodynamic damping. The focus of the study is directed toward low cost competent munitions that extend range and as such a simple flight control system is considered which utilizes only timer, roll rate, and roll attitude inputs.

  13. Probable projectile-target combinations for the synthesis of super heavy nucleus $^{286}$112

    CERN Document Server

    Santhosh, K P

    2014-01-01

    The fusion cross sections for the reactions of all the projectile-target combinations found in the cold valleys of $^{286}$112 have been studied using scattering potential as the sum of Coulomb and proximity potential, so as to predict the most probable projectile-target combinations in heavy ion fusion reactions for the synthesis of super heavy nucleus $^{286}$112. While considering the nature of potential pockets and half lives of the colliding nuclei, the systems $^{82}$Ge + $^{204}$Hg, $^{80}$Ge + $^{206}$Hg and $^{78}$Zn + $^{208}$Pb found in the deep cold valley region and the systems $^{48}$Ca+$^{238}$U, $^{38}$S+$^{248}$Cm and $^{44}$Ar+$^{242}$Pu in the cold valleys are predicted to be the better optimal projectile-target combinations for the synthesis of super heavy nucleus $^{286}$112.

  14. Meso-scale hypervelocity cratering experiments (MEMIN project): Characterization of projectile material

    Science.gov (United States)

    Domke, Isabelle; Deutsch, Alex; Hecht, Lutz; Kenkmann, Thomas; Berndt, Jasper

    2010-05-01

    The DFG-funded "MEMIN" (multidisciplinary experimental and modelling impact crater research network) research group is aimed at a better understanding of the impact cratering process by combining (i) numerical modelling of crater formation, (ii) investigation of terrestrial craters and (iii) meso-scale hypervelocity impact experiments using the large two-stage light gas gun at the Ernst-Mach-Institute (EMI; Efringen-Kirchen, Germany). In the framework of MEMIN, 1 cm-sized projectiles of the steel SAE 4130 (mass of 4.1 g) have been fired with a velocity of ~ 5.3 km s-1 onto blocks of Seeberger sandstone (size 100 x 100 x 50 cm, grain size 169+/-8 μm; porosity 12-20 vol.%). One goal of MEMIN is to document, analyze, and understand the fate of the projectile and its distribution between crater and ejecta; hence, the use of well-analyzed projectile material is mandatory. For this purpose, we use optical, and electron microscopy, electron microprobe (WWU, and MfN), and LA-ICP-MS microanalysis (WWU). Currently we evaluate which steel or iron meteorite is adequate for the intended use. Important properties of a projectile are (i) textural and chemical homogeneity, (ii) clear chemical distinction to the target sandstone, (iii) presence of elements such as Co, Ni, Cr, PGE that as "meteoritic component" are used in terrestrial craters to trace projectile matter, and characterize the type of the projectile (i.e., meteorite group), and finally (iv) mechanical properties that guarantee stability during sphere production, launch and flight. Strong chemical differences to the target material and geochemical homogeneity of the projectile will allow detection of small volumes of projectile matter by high spatial resolution in-situ analysis with the LA-ICP-MS. Steel SAE 4130 is heterogeneous at the 100-µm scale and has low trace element contents. In future, we plan the use of the alloyed heat treatable steel D290-1 as projectile as its texture is quite homogenous at the scale of

  15. Probable Projectile-Target Combinations for the Synthesis of Super Heavy Nucleus 286112

    Directory of Open Access Journals (Sweden)

    K. P. Santhosh

    2014-02-01

    Full Text Available The fusion cross sections for the reactions of all the projectile-target combinations found in the cold valleys of 286112 have been studied using scattering potential as the sum of Coulomb and proximity potential, so as to predict the most probable projectile-target combinations in heavy ion fusion reactions for the synthesis of super heavy nucleus 286112. While considering the nature of potential pockets and half lives of the colliding nuclei, the systems 82Ge + 204Hg, 80Ge + 206Hg and 78Zn + 208Pb found in the deep cold valley region and the systems 48Ca+238U, 38S+248Cm and 44Ar+242Pu in the cold valleys are predicted to be the better optimal projectile-target combinations for the synthesis of super heavy nucleus 286112.

  16. Penetration experiments in aluminum 1100 targets using soda-lime glass projectiles

    Science.gov (United States)

    Horz, Friedrich; Cintala, Mark J.; Bernhard, Ronald P.; Cardenas, Frank; Davidson, William E.; Haynes, Gerald; See, Thomas H.; Winkler, Jerry L.

    1995-01-01

    The cratering and penetration behavior of annealed aluminum 1100 targets, with thickness varied from several centimeters to ultra-thin foils less than 1 micrometer thick, were experimentally investigated using 3.2 mm diameter spherical soda-lime glass projectiles at velocities from 1 to 7 km/s. The objective was to establish quantitative, dimensional relationships between initial impact conditions (impact velocity, projectile diameter, and target thickness) and the diameter of the resulting crater or penetration hole. Such dimensional relationships and calibration experiments are needed to extract the diameters and fluxes of hypervelocity particles from space-exposed surfaces and to predict the performance of certain collisional shields. The cratering behavior of aluminum 1100 is fairly well predicted. However, crater depth is modestly deeper for our silicate impactors than the canonical value based on aluminum projectiles and aluminum 6061-T6 targets. The ballistic-limit thickness was also different. These differences attest to the great sensitivity of detailed crater geometry and penetration behavior on the physical properties of both the target and impactor. Each penetration experiment was equipped with a witness plate to monitor the nature of the debris plume emanating from the rear of the target. This plume consists of both projectile fragments and target debris. Both penetration hole and witness-plate spray patterns systematically evolve in response to projectile diameter/target thickness. The relative dimensions of the projectile and target totally dominate the experimental products documented in this report; impact velocity is an important contributor as well to the evolution of penetration holes, but is of subordinate significance for the witness-plate spray patterns.

  17. Weber numbers at various stages of water projectile transformation during free fall in air

    Science.gov (United States)

    Volkov, R. S.; Kuznetsov, G. V.; Kuibin, P. A.; Strizhak, P. A.

    2015-10-01

    The process of breakage of water projectiles (spherical "balls" with initial volumes ranging within 0.05-40.5 L) during free fall in air from a height of 3 m has been studied by means of high-speed (up to 105 fps) video recording. Four stages of projectile transformation are distinguished that precede the formation of a cloud of droplets. It is established that the transitions from one stage to another proceed within shorter fall times for greater initial volumes of water. Weber numbers at these stages are determined.

  18. Young-type interference in projectile-electron loss in energetic ion-molecule collisions

    International Nuclear Information System (INIS)

    We propose an alternative and very promising scenario for studying the Young-type-interference phenomena in energetic ion-molecule collisions. In such a scenario, we focus on the energy spectra of electrons that are ionized from the bound states of fast moving projectiles. We argue that under certain conditions these (projectile) electrons interact mainly with the nuclei and inner-shell electrons of atoms forming the molecule. Due to their compact localization in space and distinct separation from each other, these molecular centers play a role similar to that of optical slits in light scattering leading to pronounced interference patterns in electron energy distributions.

  19. Sublinear effect in light emission from cesium iodide bombarded by keV polyatomic projectiles

    Science.gov (United States)

    Baudin, K.; Parilis, E. S.; Blankenship, J. F.; Van Stipdonk, M. J.; Schweikert, E. A.

    1998-02-01

    Our experiments examined light emission from a CsI target bombarded with polyatomic projectiles [H n+, (NaF) nNa +, with n=1,2; Na +, Cs 2I +, Cs +] at 5-30 keV impact energies. The light emission increases with primary ion velocity as ( V - Vth) α, where Vth is a velocity threshold. The number of photons emitted under one cluster impact increases with the number of atoms in the projectile, displaying a sublinear effect, similar to that reported elsewhere for electron emission. The model of sweeping out electrons has been applied to explain and calculate the observed effect.

  20. Reliability of double-wall containment against the impact of hard projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, Nadeem A., E-mail: nadeem@ksu.edu.sa; Khateeb, Baha M.A.; Almusallam, Tarek H.; Abbas, Husain

    2014-04-01

    Highlights: • The reliability of double-wall containment against impact of projectiles was studied. • Probabilistic procedure based on Monte Carlo simulation technique was used. • Sensitivity studies were carried out to obtain the results of practical interest. • Reliability is correlated with the ballistic limit of the outer RC wall. - Abstract: Effectiveness of single or double-wall containment structures against a possible strike of projectiles, missiles or airplanes is well researched. However, how the uncertainties involved in the various design parameters influence the reliability of the containment is not very well known. In a double-wall containment structure, as name implies, there are two walls – an outer thick reinforced concrete (RC) wall and an inner thin steel shell/wall. In the present study, a simple probabilistic procedure based on Monte Carlo simulation technique is presented to study the reliability of double-wall containment structures against the impact of external hard projectiles on outer RC wall for varying impact velocities. In order to illustrate the proposed methodology, an idealized double-wall containment structure and a hard projectile were chosen. The probability of failure and the reliability indices of the selected double-wall containment structure were obtained for different striking velocities of the projectile and safety of the containment was correlated with the ballistic limit of the outer RC wall. The results of the study show that the double-wall containment is “safe enough” against the impact of the selected projectile if the projectile nominal velocity is less than 65% of the containment outer wall's nominal ballistic limit (V{sub BL}). Results also show that under the given uncertainties, if the nominal impact velocity is less than 65% of the nominal ballistic limit of the outer RC wall (i.e. 0.65V{sub BL}), failure probability of the containment is almost zero. However, when impact velocity is more than

  1. Model for projectile fragmentation: case study for Ni on Ta, Be and Xe on Al

    OpenAIRE

    Mallik, S.; Chaudhuri, G.; Gupta, S. Das

    2010-01-01

    For projectile fragmentation we work out details of a model whose origin can be traced back to the Bevalac era. The model positions itself between the phenomenological EPAX parametrization and microscopic transport models like "Heavy Ion Phase Space Exploration Model" (HIPSE) and antisymmetrised molecular dynamics(AMD). We apply the model to some recent data of projectile fragmentation of Ni on Ta and Be at beam energy 140 MeV/nucleon and some older data of Xe on Al at beam energy 790 MeV/nuc...

  2. Experimental and numerical studies of liquid dispersal from a soft projectile impacting a wall

    International Nuclear Information System (INIS)

    Research highlights: → Liquid erupts from a high-speed missile as a flat and uniform pattern perpendicular to the incoming direction. → Initial speed of the liquid may be much higher than the impact velocity. → The FDS software can be used to simulate the two-phase flows involving high-speed droplets. - Abstract: A medium-scale IMPACT test programme is currently being implemented at the Technical Research Centre of Finland (VTT). In these tests, deformable cylindrical steel or aluminium projectiles impact a solid concrete wall or a steel force plate. One part of the test is conducted with a missile filled with liquid water to study liquid dispersal phenomena (i.e., wet missile tests). The fluid-filled missile ranged in length from 0.5 to 1.5 m, the water mass inside the missile from 15 to 68 kg, and the impact velocity of missile from 70 to 177 m/s. This paper describes the methods used to measure the liquid dispersal processes, and presents the main results for preliminary simulations of liquid spread. Because the IMPACT tests have focused on structural aspects, it was necessary to develop cost-effective methods for measuring liquid phenomena. The tests measured some important parameters associated with liquid: the discharge speed and direction of the liquid core released from the ruptured missile, propagation speed of the spray front, liquid pooling on the floor, extent of liquid dispersal away from the target, and the drop size of the liquid spray. The experimental findings indicate that the liquid release starts along the surface almost perpendicularly to the incoming direction of the missile and forms a fairly 'flat' and uniform splash pattern around the missile. Although the discharge speed of the liquid core may be initially much higher than the impact velocity of the missile, the propagation speed of the spray front decreases rapidly with increasing distance from the source. Results of the preliminary simulations show that the Fire Dynamic Simulator

  3. The African Origin of Complex Projectile Technology: An Analysis Using Tip Cross-Sectional Area and Perimeter

    Directory of Open Access Journals (Sweden)

    Matthew L. Sisk

    2011-01-01

    Full Text Available Despite a body of literature focusing on the functionality of modern and stylistically distinct projectile points, comparatively little attention has been paid to quantifying the functionality of the early stages of projectile use. Previous work identified a simple ballistics measure, the Tip Cross-Sectional Area, as a way of determining if a given class of stone points could have served as effective projectile armatures. Here we use this in combination with an alternate measure, the Tip Cross-Sectional Perimeter, a more accurate proxy of the force needed to penetrate a target to a lethal depth. The current study discusses this measure and uses it to analyze a collection of measurements from African Middle Stone Age pointed stone artifacts. Several point types that were rejected in previous studies are statistically indistinguishable from ethnographic projectile points using this new measure. The ramifications of this finding for a Middle Stone Age origin of complex projectile technology is discussed.

  4. Eulerian simulation of the perforation of aluminum plates by nondeforming projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Silling, S.A.

    1992-03-01

    A new algorithm for the treatment of sliding interfaces between solids with or without friction in an Eulerian wavecode is described. The algorithm has been implemented in the two-dimensional version of the CTH code. The code was used to simulate penetration and perforation of aluminum plates by rigid, conical-nosed tungsten projectiles. Comparison with experimental data is provided.

  5. The Effect of Cooperative Learning on Grade 12 Learners' Performance in Projectile Motions, South Africa

    Science.gov (United States)

    Kibirige, Israel; Lehong, Moyahabo Jeridah

    2016-01-01

    The study explored the effect of cooperative learning on Grade 12 learners' performance in projectile motions. A quasi-experimental research design with non-equivalent control group was used. Two schools were purposively selected from Maleboho Central circuit in South Africa based on their performance in Physical Sciences Grade 12 results of 2011.…

  6. Amazing Physics: Learning about Work, Energy and Projectile Motion in a Historical Context

    Science.gov (United States)

    Tural, Guner

    2013-01-01

    Teaching physics through a historical context provides effective learning and increases students' motivation for and interest in physics. For example, trebuchets and mangonels may be interesting historical contexts for learning about energy, work, and projectile motion. In this study, the implementation of physics lessons related to these…

  7. A heavy ion spectrometer system for the measurement of projectile fragmentation of relativistic heavy ions

    International Nuclear Information System (INIS)

    The Heavy Ion Spectrometer System (HISS) at the LBL Bevalac provided a unique facility for measuring projectile fragmentation cross sections important in deconvolving the Galactic Cosmic Ray (GCR) source composition. The general characteristics of the apparatus specific to this application are described and the main features of the event reconstruction and analysis used in the TRANSPORT experiment are discussed

  8. Breakup of the projectile in heavy ion collisions at intermediate energies

    International Nuclear Information System (INIS)

    Report on an experiment in which the 4He breakup channel of 16O projectiles on various targets (27Al, 58Ni, 197Au) has been studied inclusively, and exclusively (in coincidence with charged pions). The bombarding energy was 94 MeV/nucleon. (D.L.). 7 refs., 5 figs

  9. Wound Ballistics: Study of the Rupture of Human Skin Membrane under the Impact of a Projectile

    Directory of Open Access Journals (Sweden)

    M. Jauhari

    1979-07-01

    Full Text Available The paper attempts to theorize the rupture of human skin membrane under the impact of a projectile. An expression for the threshold velocity for penetration has been derived which is found to give results in fair agreement with experimental values reported in literature.

  10. Tissue simulant response at projectile impact on flexible fabric armour systems

    NARCIS (Netherlands)

    Bree, J.L.M.J. van; Volker, A.; Heiden, N. van der

    2006-01-01

    Behind Armour Blunt Trauma is a phenomenon which has been studied extensively for rigid personal protective armour systems. These systems used in e.g. bullet proof vests manage to defeat high velocity small arms projectiles. Tissue simulants are used to study behind armour effects. At high velocity

  11. Estimating the excitation energy of the primary projectile like fragments in a dissipative binary collision

    International Nuclear Information System (INIS)

    In the present study, we have tried to estimate the excitation energy of the primary projectile like fragments (PLFs) using the experimental data as well as simulation for the reaction 48Ca + 124Sn at 45 A MeV of lab energy

  12. Energy distribution of the particles obtained after irradiation of carbon nanotubes with carbon projectiles

    International Nuclear Information System (INIS)

    The idea of using carbon nanotubes (CNTs) as masks against irradiation has recently emerged, because of the region of a given material covered by a CNT can be protected from the effects of irradiation, creating nanowires. In this case, it is interesting to know in detail the number of generated recoils and their energy. In order to obtain these data, we simulate the irradiation of CNTs with carbon ions using a molecular dynamics code. To describe the interaction between carbon ions we use the Brenner potential joined smoothly to the Universal ZBL potential at short distances. We have analyzed the energy distributions of the carbon atoms emerging from the CNT for single projectile irradiation with incident energies from 30 eV to 5 keV. Our results show that the number and the energy of the recoil carbon atoms emerging from the CNT increases with the projectile incident energy. In average, each projectile with incident energy of 1 keV produces ∼3.6 recoils, which have a mean energy of 150 eV, while projectiles with 5 keV produce ∼7 recoils with a mean energy of 400 eV

  13. On projectile fragmentation at high-velocity perforation of a thin bumper

    Science.gov (United States)

    Myagkov, N. N.; Stepanov, V. V.

    2014-09-01

    By means of 3D numerical simulations, we study the statistical properties of the fragments cloud formed during high-velocity impact of a spherical projectile on a mesh bumper. We present a quantitative description of the projectile fragmentation, and study the nature of the transition from the damage to the fragmentation of the projectile when the impact velocity varies. A distinctive feature of the present work is that the calculations are carried out by smoothed particle hydrodynamics (SPH) method applied to the equations of mechanics of deformable solids (MDS). We describe the materials behavior by the Mie-Grüneisen equation of state and the Johnson-Cook model for the yield strength. The maximum principal stress spall model is used as the fracture model. It is shown that the simulation results of fragmentation based on the MDS equations by the SPH method are qualitatively consistent with the results obtained earlier on the basis of the molecular dynamics and discrete element models. It is found that the power-law distribution exponent does not depend on energy imparted to the projectile during the high-velocity impact. At the same time, our calculations show that the critical impact velocity, the power-law exponent and other critical exponents depend on the fracture criterion.

  14. Production and transport of the excited states of projectile ions in ion-solid interaction

    International Nuclear Information System (INIS)

    In ion-solid collisions, more excited states of projectile ions with high angular momenta l are populated than in ion-atom collisions. The use of 13.6 MeV/u Ar18+ projectile ions and solid carbon targets allowed us to study Ar17+ excited states initially populated by electron capture. Using various targets with increasing thickness from 3.5 to 200 μg/cm2, the evolution of excited states from the single collision condition to the population equilibrium was investigated. We observed the evolution of the Lyman line intensities as a function of the ion transit time inside the target (sensitive to core state population) and as a function of the ion time of flight behind the target (sensitive to Rydberg state population). To explain the experimental results, a complete theoretical analysis of the transport of excited states inside the medium was performed. We used two different collisional models. The first one is a rate equation model based on a statistical description of binary collisions of the projectile with target atoms. The second one is a classical transport theory based on an equation describing the motion of the projectile electron on a classical orbit perturbed by a stochastic force. A comparison with experiment shows that such a collisional approach allows to interpret the excited l-state population, but fails in describing the core state population. The observed l mixing in these states is much larger than predicted by the models. The polarization of the medium induced by the projectile ion, with both models do not take into account, could be responsible for this mixing by means of the Stark effect. (author)

  15. Experimental study of the expansion dynamic of 9 mm Parabellum hollow point projectiles in ballistic gelatin.

    Science.gov (United States)

    Bresson, F; Ducouret, J; Peyré, J; Maréchal, C; Delille, R; Colard, T; Demondion, X

    2012-06-10

    We study in this paper the expanding behaviour of hollow point 9 mm Parabellum projectiles (Hornady XTP(®) and Speer Gold Dot(®)). We defined a deformation rate that takes into account both the diameter increase and the length reduction. We plotted the behaviour of this parameter versus impact velocity (we refer to this curve as the expanding law). This expanding law has been plotted for different gelatin weight ratios and different gelatin block lengths. We completed our experiments with a set of high speed movies in order to correlate the deceleration to the state of expansion and size of the temporary cavity. Our results pointed out that full expansion is reached shortly after the projectile fully penetrates the gelatin. This result shows that the key point to accurately simulate human body interaction with a hollow point projectile is to accurately simulate the interface (skin, skull, clothes thoracic walls). Simulating accurately organs is only an issue if a quantitative comparison between penetration depths is required, but not if we only focus on the state of expansion of the projectile. By varying the gelatin parameters, we discovered that the expanding law exhibits a velocity threshold below which no expansion occurs, followed by a rather linear curve. The parameters of that expanding law (velocity threshold and line slope) vary with the gelatin parameters, but our quantitative results demonstrate that these parameters are not extremely critical. Finally, our experiments demonstrate that the knowledge of the expansion law can be a useful tool to investigate a gunshot in a human body with a semi-jacketed projectile, giving an estimation of the impact velocity and thus the shooting distance. PMID:22269130

  16. INVESTIGATION OF GLASS PLATE FAILURE MECHANISM SUBJECTED TO COPPER AND STEEL PROJECTILE IMPACTS

    Directory of Open Access Journals (Sweden)

    Qasim H. Shah

    2014-05-01

    Full Text Available Normal 0 false false false EN-US JA X-NONE ABSTRACT: A glass plate was subjected to impact by spherical copper and steel projectiles at low velocities. The glass failure features consisted of a central Hertzian cone made up of comminuted glass and a spider web like cracking pattern around the cone with circumferential and radial cracks. The objective of the investigation was to determine if the damage caused by copper projectile impact compared to steel projectile impact was higher for the same kinetic energy (K.E. projectiles and the reason for this phenomenon. For the constant K.E. impact, copper projectile apparently caused higher damage in glass plate. Higher damage was attributed to projectile contact duration and the contact area between the projectile and the glass plate. Finite element analysis using LS-DYNA based upon maximum principal strain failure criterion for laminated glass model was able to predict the failed material under the impact location and the cracking pattern in the glass plate for a biased meshing scheme. Radial cracks in glass target were reported to be 15% higher for copper projectile impact than the steel projectile impact. ABSTRAK: Kepingan kaca dikenakan impak oleh projektil kuprum dan keluli berbentuk sfera pada halaju rendah. Ciri-ciri kegagalan kaca terdiri daripada kon berpusat Hertzian yang melibatkan kaca yang hancur dan corak pecahan berbentuk sesawang lelabah pada keliling kon dengan retakan lilitan dan jejarian. Tujuan penyelidikan adalah untuk menentukan sebab bagaimana  dengan projektil tenaga kinetik yang sama, kerosakan yang diakibatkan oleh impak projektil kuprum berbanding dengan impak projektil keluli adalah lebih tinggi. Untuk impak tenaga kinetik yang malar, projektil kuprum didapati menyebabkan kerosakan yang lebih ke atas kepingan kaca. Kerosakan lebih disebabkan oleh tempoh sentuhan projektil dan kawasan sentuhan di antara projektil dan kepingan kaca. Analisis unsur terhingga menggunakan LS

  17. MULTIPLE IONIZATION PROCESS STUDIED WITH COINCIDENCE TECHNIQUE BETWEEN SLOW RECOIL ION AND PROJECTILE ION IN 42 MeV Arq+—Ar COLLISIONS

    Institute of Scientific and Technical Information of China (English)

    T.Tonuma; T.Matsuo; 等

    1990-01-01

    Slow Ar recoil ion Production cross sections by 42 MeV Ar1+(q=4-14) projectiles were measured using a projectile ion-recoilion coincidence technique in order to provide information on mechanisms of multiple ionization of target atome through pure ionization as well as of that accompaied simultaneously with multiple electron loss or capture of projectiles.The present results suggest that inner-shell electron processes caused through electron transfer into projectiles and also electron ionization by projectiles play a key role in the production of multiply charged recoil ions.

  18. Multifragmentation induced by light relativistic projectiles and heavy ions: similarities and differences

    International Nuclear Information System (INIS)

    The experimental data on fragment multiplicities, their energy and charge distributions, the emission times are considered for the nuclear multifragmentation process induced by relativistic light projectiles (protons, helium) and heavy ions. With light projectiles, the multifragmentation is a pure 'thermal' process, well described by the statistical models. Heavy-ion-induced multifragmentation is influenced by dynamic effects related first of all to the compression of the system in the collision. But statistical models can also be applied to rendering the partition of the system if the excitation energy is less than 10 MeV/nucleon and compression is modest. For the central collision of heavy ions the statistical approach fails to describe the data

  19. Excitation and decay of projectile-like fragments formed in dissipative peripheral collisions at intermediate energies

    CERN Document Server

    Yañez, R; Alfaro, R; Davin, B; Larochelle, Y; Xu, H; Beaulieu, L; Lefort, T; Viola, V E; De Souza, R T; Liu, T X; Liu, X D; Lynch, W G; Shomin, R; Tan, W P; Tsang, M B; Molen, A V; Wagner, A; Xi Hong Fei; Charity, R J; Sobotka, L G

    2003-01-01

    Projectile-like fragments (PLF:15<=Z<=46) formed in peripheral and mid-peripheral collisions of 114Cd projectiles with 92Mo nuclei at E/A=50 MeV have been detected at very forward angles, 2.1 deg.<=theta_lab<=4.2 deg. Calorimetric analysis of the charged particles observed in coincidence with the PLF reveals that the excitation of the primary PLF is strongly related to its velocity damping. Furthermore, for a given V_PLF*, its excitation is not related to its size, Z_PLF*. For the largest velocity damping, the excitation energy attained is large, approximately commensurate with a system at the limiting temperature

  20. Statistical fragmentation of Au projectiles at E/A=600 MeV

    International Nuclear Information System (INIS)

    The mean multiplicity of intermediate mass fragments (MIMF) produced by fragmentation of Au projectiles interacting with targets of C, Al, Cu and Pb at an incident energy of E/A = 600 MeV is compared to predictions of statistical multifragmentation and sequential evaporation models. The initial conditions for the calculations were provided by BUU simulations. In the high excitation energy regime the observed universal correlation between (MIMF) and the total charge Zbound of projectile fragments with charges Z ≥ 2 can not be reprocuced by the sequential evaporation code GEMINI. The data are well described by statistical decay calculations which assume the formation of an expanded nuclear system and a rather fast break-up. (orig.)

  1. Effect of target deformation and projectile breakup in complete fusion of 6Li + 152Sm

    International Nuclear Information System (INIS)

    Nuclear reaction induced by weakly bound (stable or radioactive) nuclei is a subject of current experimental and theoretical interest. Measurements of fusion cross section involving loosely bound projectile 6Li and 9Be exist with different conclusion about the enhancement or suppression of fusion cross section. Recently we have measured the fusion cross section for 6Li + 144Sm, where it has been found that there is an enhancement of fusion cross section below the barrier in comparison with single BPM calculation, where as there is an overall suppression in fusion cross section as compared to CCFULL calculation in the entire energy range measured. With this motivation, we chose a deformed target, 152Sm, with β2 = 0.24 to compare with the results of 144Sm which is a spherical target. It will also be interesting to see effect of target deformation (enhancement) versus projectile breakup (suppression) specially at subbarrier energy

  2. Angry Birds realized: water balloon launcher for teaching projectile motion with drag

    International Nuclear Information System (INIS)

    A simple, collapsible design for a large water balloon slingshot launcher features a fully adjustable initial velocity vector and a balanced launch platform. The design facilitates quantitative explorations of the dependence of the balloon range and time of flight on the initial speed, launch angle, and projectile mass, in an environment where quadratic air drag is important. Presented are theory and experiments that characterize this drag, and theory and experiments that characterize the nonlinear elastic energy and hysteresis of the latex tubing used in the slingshot. The experiments can be carried out with inexpensive and readily available tools and materials. The launcher provides an engaging way to teach projectile motion and elastic energy to students of a wide variety of ages. (paper)

  3. An approach for considering ionization of light atoms by relativistic projectiles generating strong electromagnetic fields

    International Nuclear Information System (INIS)

    We propose an approach to treat ionization of light atoms in relativistic collisions with highly charged ions, where the electromagnetic field generated by the ions can be very strong. The approach is based on the observation that, for a collision with a certain momentum transfer, either the relativistic effects, connected with the collision velocity approaching the speed of light, or the higher-order terms in the corresponding Born series in the projectile-target interaction can be of importance for the ionization process. The approach consists of dividing all collisions into those with 'small' and 'large' momentum transfers, which are described by (the first order of) the relativistic Born and the Glauber approximations, respectively. The approach is applied to describe helium single ionization by 1 GeV u-1 U92+ projectiles

  4. Effect of projectile structure on evaporation residue yields in incomplete fusion reactions

    International Nuclear Information System (INIS)

    The excitation functions of heavy residues, representing complete and incomplete fusion products, produced in the reaction of 12C and 13C on 181Ta have been measured over the projectile energy range of 5 to 6.5 MeV/nucleon by the recoil catcher method and off-line γ-ray spectrometry. Comparison of the measured excitation functions with those calculated using the PACE2 code based on the statistical model revealed the occurrence of incomplete fusion reactions in the formation of α emission products. The fraction of incomplete fusion cross sections in the 12C + 181Ta reaction was found to be higher, by a factor of ∼2, than that in the 13C + 181Ta reaction. The results have been discussed in terms of the effect of alpha cluster structure of the projectile on incomplete fusion reactions

  5. Projectile charge and velocity effect on UO2 sputtering in the nuclear stopping regime

    International Nuclear Information System (INIS)

    Angular distributions and yields of uranium sputtered by slow highly charged Xeq+ ions (kinetic energy 1.5 keV ≤ Ek ≤ 81 keV, charge state 1 ≤ q ≤ 25 ) from UO2 were measured by means of the catcher technique. A charge state effect on the sputtering process is observed at 8 and 81 keV. A deviation from a A*cos(θ) shape (the linear collision cascade theory) is observed in case of Xeq+ impinging a UO2 surface at Ek = 8 keV. Yields increase linearly with projectile charge state q thus clearly revealing the contribution of potential energy to the sputtering process. In addition, as the kinetic energy of a Xe10+ projectile decreases from 81 keV to 1.5 keV, a velocity effect is clearly observed on the angular distribution. (authors)

  6. Fragmentation cross section measurements of iron projectiles using CR-39 plastic nuclear track detectors

    CERN Document Server

    Flesch, F; Huentrup, G; Roecher, H; Streibel, T; Winkel, E; Heinrich, W

    1999-01-01

    For long term space missions in which larger radiation doses are accumulated it is necessary to improve the precision of models predicting the space radiation environment. Different models are available to determine the flux of cosmic ray heavy ions behind shielding material. The accuracy of these predictions depends on the knowledge of the fragmentation cross sections, especially at energies of several hundred MeV/nucleon, where the particle flux is at a maximum and especially for those particles with high LET, i.e. iron nuclei. We have measured fragmentation cross sections of sup 5 sup 6 Fe projectiles at beam energies of 700 and 1700 A MeV using experimental set-ups with plastic nuclear track detectors. In this paper we describe the experimental technique to study the fragmentation reactions of sup 5 sup 6 Fe projectiles using CR-39 plastic nuclear track detectors. Results for different targets are presented.

  7. Electron-hydrogen collisions with dressed target and Volkov projectile states in a laser field

    International Nuclear Information System (INIS)

    Cross sections for the 1S-2S and 1S-2PO transitions in laser-assisted e--H(1S) collisions are calculated in both the multi-channel eikonal treatment and the Born wave approximation, as a function of impact energy and laser field intensity. The laser considered is a monotonic, plane-polarized CO2 laser (photon energy = 0.117 eV) with the polarization direction parallel to the initial projectile velocity. The first part of this paper confines the laser perturbation to the bound electrons of the atom. The second part extends the laser perturbation to the projectile electron, and the familiar Volkov dressed states are used. (author)

  8. A NASTRAN investigation of simulated projectile damage effects on a UH-1B tail boom model

    Science.gov (United States)

    Futterer, A. T.

    1980-01-01

    A NASTRAN model of a UH-1B tail boom that had been designed for another project was used to investigate the effect on structural integrity of simulated projectile damage. Elements representing skin, and sections of stringers, longerons and bulkheads were systematically deleted to represent projectile damage. The structure was loaded in a manner to represent the flight loads that would be imposed on the tail boom at a 130 knot cruise. The deflection of four points on the rear of the tail boom relative to the position of these points for the unloaded, undamaged condition of the tail boom was used as a measure of the loss of structural rigidity. The same procedure was then used with the material properties of the aluminum alloys replaced with the material properties of T300/5208 high strength graphite/epoxy fibrous composite material, (0, + or - 45, 90)s for the skin and (0, + or - 45)s for the longerons, stringers, and bulk heads.

  9. Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes

    CERN Document Server

    Thies, R; Adachi, T; Aksyutina, Y; Alcantara-Núñes, J; Altstadt, S; Alvarez-Pol, H; Ashwood, N; Aumann, T; Avdeichikov, V; Barr, M; Beceiro-Novo, S; Bemmerer, D; Benlliure, J; Bertulani, C A; Boretzky, K; Borge, M J G; Burgunder, G; Caamano, M; Caesar, C; Casarejos, E; Catford, W; Cederkäll, J; Chakraborty, S; Chartier, M; Chulkov, L V; Cortina-Gil, D; Crespo, R; Datta, U; Fernández, P Díaz; Dillmann, I; Elekes, Z; Enders, J; Ershova, O; Estradé, A; Farinon, F; Fraile, L M; Freer, M; Freudenberger, M; Fynbo, H O U; Galaviz, D; Geissel, H; Gernhäuser, R; Göbel, K; Golubev, P; Diaz, D Gonzalez; Hagdahl, J; Heftrich, T; Heil, M; Heine, M; Henriques, A; Holl, M; Ickert, G; Ignatov, A; Jakobsson, B; Johansson, H T; Jonson, B; Kalantar-Nayestanaki, N; Kanungo, R; Kelic-Heil, A; Knöbel, R; Kröll, T; Krücken, R; Kurcewicz, J; Kurz, N; Labiche, M; Langer, C; Bleis, T Le; Lemmon, R; Lepyoshkina, O; Lindberg, S; Machado, J; Marganiec, J; Maroussov, V; Mostazo, M; Movsesyan, A; Najafi, A; Nilsson, T; Nociforo, C; Panin, V; Paschalis, S; Perea, A; Petri, M; Pietri, S; Plag, R; Prochazka, A; Rahaman, A; Rastrepina, G; Reifarth, R; Ribeiro, G; Ricciardi, M V; Rigollet, C; Riisager, K; Röder, M; Rossi, D; del Rio, J Sanchez; Savran, D; Scheit, H; Simon, H; Sorlin, O; Stoica, V; Streicher, B; Taylor, J T; Tengblad, O; Terashima, S; Togano, Y; Uberseder, E; Van de Walle, J; Velho, P; Volkov, V; Wagner, A; Wamers, F; Weick, H; Weigand, M; Wheldon, C; Wilson, G; Wimmer, C; Winfield, J S; Woods, P; Yakorev, D; Zhukov, M V; Zilges, A; Zuber, K

    2016-01-01

    Background: Models describing nuclear fragmentation and fragmentation-fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool to reach the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from 10,12-18C and 10-15B isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent dataset. We compare our data to model calculations. Results: One-proton removal cross sec...

  10. Experimental and Numerical Correlation of Impact of Spherical Projectile for Damage Analysis of Aero Engine Component

    Directory of Open Access Journals (Sweden)

    Anuradha Nayak Majila

    2016-03-01

    Full Text Available Studies the impact response of flat Titanium alloy plate against spherical projectile for damage analysis of aero engine components using experimental and finite element techniques. Compressed gas gun has been used to impart speed to spherical projectile at various impact velocities for damage studies. Crater dimensions (diameter and depth obtained due to impact have been compared with finite element results using commercially available explicit finite element method code LS-DYNA. Strain hardening, high strain rate and thermal softening effect along with damage parameters have been considered using modified Johnson-Cook material model of LS-DYNA. Metallographic analysis has been performed on the indented specimen. This analysis is useful to study failure analysis of gas turbine engine components subjected to domestic object damage of gas turbine engine. Defence Science Journal, Vol. 66, No. 2, March 2016, pp. 193-199, DOI: http://dx.doi.org/10.14429/dsj.66.9130

  11. HIFI: a computer code for projectile fragmentation accompanied by incomplete fusion

    International Nuclear Information System (INIS)

    A brief summary of a model proposed to describe projectile fragmentation accompanied by incomplete fusion and the instructions for the use of the computer code HIFI are given. The code HIFI calculates single inclusive spectra, coincident spectra and excitation functions resulting from particle-induced reactions. It is a multipurpose program which can calculate any type of coincident spectra as long as the reaction is assumed to take place in two steps

  12. A Physical Model of Electromagnetic Force from PEMA Acted on Metal Projectiles

    Institute of Scientific and Technical Information of China (English)

    HU Jin-suo; YANG Zuo-bin

    2007-01-01

    Electromagnetic armor is a new conceptual combat vehicle technology, which improves remarkably the defensive capability and maneuverability of vehicles. The authors present definitely to apply the electromagnetic theory to analyze the electromagnetic armor. Based on electromagnetics, the experienced expression of projectile and the physical model of PEMA (passive electromagnetic armor) are obtained when electric current flows through the system, and a computer simulation is given.

  13. Recent Precision Experiments with Exotic Nuclei Produced with Uranium Projectiles and Experimental Prospects at Fair

    OpenAIRE

    Geissel H.; Chen L.; Dickel T.; Farinon F.; Dillmann I.; Knöbel R.; Kurcewicz J.; Mukha I.; Münzenberg G.; Nociforo C.; Patyk Z.; Pietri S.; Plass W.R.; Prochazka A.; Scheidenberger C.

    2014-01-01

    Precision experiments with relativistic fragments separated in-flight require special experimentalmethods to overcome the inherent large emittance from the creation in nuclear reactions and atomic interactions in matter. At GSI relativistic exotic nuclei have been produced via uranium projectile fragmentation and fission and investigated with the inflight separator FRS directly, or in combination with either the storage-cooler ring ESR or the FRS Ion Catcher. 1000 A·MeV 238U ions were used to...

  14. Symmetric eikonal model for projectile-electron excitation and loss in relativistic ion-atom collisions

    OpenAIRE

    Voitkiv, A. B.; Najjari, B.; Shevelko, S. P.

    2010-01-01

    At impact energies $ \\stackrel{>}{\\sim}1$ GeV/u the projectile-electron excitation and loss occurring in collisions between highly charged ions and neutral atoms is already strongly influenced by the presence of atomic electrons. In order to treat these processes in collisions with heavy atoms we generalize the symmetric eikonal model, used earlier for considerations of electron transitions in ion-atom collisions within the scope of a three-body Coulomb problem. We show that at asymptotically...

  15. Devices for launching 0.1-g projectiles to 150 km/s or more to initiate fusion. Pt. 2

    International Nuclear Information System (INIS)

    The possibility of using a railgun accelerator to launch 0.1-g projectiles to hypervelocities (150 km/s or more) to initiate thermonuclear fusion is explored. The analysis reveals that a railgun with a plasma-arc armature is a viable approach to the goal. When calculating the railgun's probable performance, it was discovered that this launch system might possibly be designed to avoid adverse effects from boundary layer drag. An appendix provided by A.C. Buckingham summarizes his calculations that predict the amount of erosive drag between projectile and rail. Finally, it was found that certain properties of railgun and projectile materials can impose operational limits. Using these limits, a single- and multistage accelerator was designed. Within such limits, a railgun could accelerate a 0.1-g projectile to hypervelocities. (orig.)

  16. Production of helium projectile fragments in 16O-emulsion interactions at 4.5 A GeV/c

    Institute of Scientific and Technical Information of China (English)

    Zhang Dong-Hai; Li Zhen-Yu; Li Jun-Sheng; Wu Feng-Juan

    2004-01-01

    The measurements of partial production cross sections of the multiple helium projectile fragments emitted at 4.5A GeV/c 16O-Em interactions are reported. We have studied the production rate of helium projectile fragments due to fragmentation of 16O ions and compared it with that obtained from different projectiles at various energies. The dependence of on the mass number of the incident beams is formulated. The multiplicity distributions of the helium fragments produced in 16O-Em interactions at different energies exhibit Koba-Nielson-Olesen (KNO) scaling.The correlation of helium projectile fragments and target fragments is also investigated and it is found that the average of target fragments is increased with the decrease of the number of helium fragments in peripheral interactions.

  17. Study on Visual Simulation of Terminal-Sensitive Projectile%末敏弹的可视化仿真研究

    Institute of Scientific and Technical Information of China (English)

    邱荷; 刘荣忠; 郭锐; 张俊

    2013-01-01

    Study on the visualization of tracking and control of Terminal-sensitive Projectile in motion. Because terminal-sensitive projectile will open its parachute and wing during the movement, and its law of motion of the external ballistics are very different from conventional guided missiles, so there are some difficulties to construct its visual simulation test platform. According to the structure characteristics of typical terminal-sensitive projectile and movement characteristics of the deceleration and rotary stage, this paper presented a method of visual simulation using Sim-ulink/Matlab and VR technology. The simulation results have shown that the model of visual simulation system built by using this method is accurate, the scene is vivid, and the system has good characteristics of real—time and controllability. The motion process of the stage of deceleration and rotary is reproduced well, and the result can provide some technical support for development and tactical training of terminal—sensitive projectile.%研究末敏弹运动的实时跟踪与控制问题.因为末敏弹在运动过程中要打开减速伞与减旋翼,外弹道运动规律与常规制导导弹有很大的不同,因此构建末敏弹可视化仿真试验平台有一定的难度.根据典型末敏弹的结构特点及减速减旋段的运动特性,提出了一种利用Simulink/Matlab和VR技术对其进行可视化仿真研究的方法.仿真结果表明,利用上述方法建立的可视化仿真系统模型准确,三维视景逼真,并具有良好的实时性和可控性,很好地再现了末敏弹减速减旋段运动过程,可以为末敏弹的研制和战术训练提供技术支持.

  18. Role of Projectile Degrees of Freedom in Sub-Barrier Fusion Dynamics

    Science.gov (United States)

    Gautam, Manjeet Singh

    2016-04-01

    This work theoretically investigates the role of the projectile degrees of freedom on the fusion dynamics of various heavy-ion fusion reactions. The impact of the projectile breakup channel is studied for the fusion mechanism of the 4 9 Be + 39 89 Y, 6 12 C + 39 89 Y, and 16 32,34 S + 39 89 Y reactions within the view of the coupled channel approach and the energy-dependent Woods-Saxon potential model (EDWSP model). The above-barrier fusion cross-section data of the 4 9 Be + 39 89 Y reaction is suppressed by about 20 % with respect to the theoretical predictions of the coupled channel approach and the single barrier penetration model while this suppression factor is reduced to 10 % within the context of the EDWSP model calculations. Such fusion hindrance at above-barrier energies can be understood in terms of the projectile breakup effects that arise due to its low breakup threshold. However, the observed fusion enhancement of the 6 12 C + 39 89 Y and 16 32,34 S + 39 89 Y reactions, wherein the colliding pairs are stable against breakup, is adequately explained by the EDWSP model and the coupled channel approach in the whole range of energy around the Coulomb barrier. This reveals that the energy dependence in the nucleus-nucleus potential governs barrier modification effects (barrier height, barrier position, barrier curvature) in closely similar way as reflected from the coupled channel formulation.

  19. Influence of impact conditions on plasma generation during hypervelocity impact by aluminum projectile

    Science.gov (United States)

    Song, Weidong; Lv, Yangtao; Li, Jianqiao; Wang, Cheng; Ning, Jianguo

    2016-07-01

    For describing hypervelocity impact (relative low-speed as related to space debris and much lower than travelling speed of meteoroids) phenomenon associated with plasma generation, a self-developed 3D code was advanced to numerically simulate projectiles impacting on a rigid wall. The numerical results were combined with a new ionization model which was developed in an early study to calculate the ionized materials during the impact. The calculated results of ionization were compared with the empirical formulas concluded by experiments in references and a good agreement was obtained. Then based on the reliable 3D numerical code, a series of impacts with different projectile configurations were simulated to investigate the influence of impact conditions on hypervelocity impact generated plasma. It was found that the form of empirical formula needed to be modified. A new empirical formula with a critical impact velocity was advanced to describe the velocity dependence of plasma generation and the parameters of the modified formula were ensured by the comparison between the numerical predictions and the empirical formulas. For different projectile configurations, the changes of plasma charges with time are different but the integrals of charges on time almost stayed in the same level.

  20. Systematic model-dependent behaviour of fusion involving weakly bound projectiles 6,7Li

    International Nuclear Information System (INIS)

    Many measurements on complete fusion (CF) cross section at above barrier energies involving weakly bound stable projectiles (e.g., 6Li, 7Li and 9Be) show suppression by various degrees compared to theoretical estimates as well as experimental CF cross sections of reactions involving strongly bound projectiles. However, there is no concrete picture at sub-barrier energies. The conclusions based on coupled-channels (CC) calculations using different codes (e.g., FRESCO or CCFULL) may differ as the theoretical models used to calculate fusion are not same. In a recent paper on complete fusion in 7Li+152Sm system, the fusion cross sections calculated by CCFULL and FRESCO have been shown to be different despite using same bare potential. It was observed that with the inclusion of only inelastic couplings, the results of FRESCO were much closer to the experimental data in the above barrier region, while the CCFULL results overpredict the data over the entire range. To explore the above observation in different systems involving 6,7Li as projectile, in the present work, a systematic and detailed study has been carried out by means of CC calculations using both FRESCO and CCFULL. The aim is to analyze the differences between the two models of calculations

  1. INTERACTION MEAN FREE PATH OF He PROJECTILE FRAGMENTS FROM 16O-EM COLLISION AT 60 A GeV

    Institute of Scientific and Technical Information of China (English)

    ZHANG DONG-HA1; SUN HAN-CHENG; G.GHARIBI

    2001-01-01

    The interaction mean free path of He projectile fragments, produced by the collisions of 16O at 60 A GeV in a nuclear emulsion, has been investigated. In the present analysis, 1555 He projectile fragments, giving rise to 320 secondary interactions, have been used. At a level of 3% a very weak signal of anomalons is observed, which comes mainly from the 3×He channel.

  2. Characteristics of charged projectile fragments from 24Mg-emulsion interactions at 4.5 A GeV/c

    International Nuclear Information System (INIS)

    A total sample of 1719 inelastic interactions of 24Mg in emulsion at 4.5 A GeV/c has been used to study the characteristics of projectile fragments. The multiplicity and angular distributions of projectile fragments in interactions with different target components have been investigated. The projected angular distributions of fragments exhibit features of limiting fragmentation. These distributions are consistent with quantum-mechanical calculations using the Sudden approximation and shell-model functions

  3. The study of quasi-projectiles produced in Ni+Ni and Ni+Au collisions: excitation energy and spin

    International Nuclear Information System (INIS)

    During the collision between the projectile and the target nuclei in the intermediate energy regime (E < 100 MeV/nucleon) two excited nuclei are mainly observed in the exit channel, the quasi projectile (QP) and the quasi target. They disintegrate by particle emission. However, this binary picture is perturbed by the emission of particles and light fragments with velocities intermediate between the projectile velocity and the target one, all along the interaction (midrapidity component). This work aim to determine the excitation energy and the intrinsic angular momentum (or spin) of quasi-projectiles produced in the Ni+Ni and Ni+Au collisions at 52 and 90 MeV/nucleon. The excitation energy is deduced from the kinematical characteristics of particles emitted by the quasi-projectile. They have to be separated from midrapidity particles. Three different scenarios have been used for this purpose. The spin of the quasi-projectile has been extracted from the experimental data by mean of proton and alpha particles multiplicities emitted by the QP in the Ni+Au at 52 MeV/nucleon reaction. The results have been compared to the predictions of a theoretical model based on nucleon transfers. Their evolution is qualitatively reproduced as a function of the violence of the collision. (author)

  4. The motion of an arbitrarily rotating spherical projectile and its application to ball games

    International Nuclear Information System (INIS)

    In this paper the differential equations which govern the motion of a spherical projectile rotating about an arbitrary axis in the presence of an arbitrary ‘wind’ are developed. Three forces are assumed to act on the projectile: (i) gravity, (ii) a drag force proportional to the square of the projectile's velocity and in the opposite direction to this velocity and (iii) a lift or ‘Magnus’ force also assumed to be proportional to the square of the projectile's velocity and in a direction perpendicular to both this velocity and the angular velocity vector of the projectile. The problem has been coded in Matlab and some illustrative model trajectories are presented for ‘ball-games’, specifically golf and cricket, although the equations could equally well be applied to other ball-games such as tennis, soccer or baseball. Spin about an arbitrary axis allows for the treatment of situations where, for example, the spin has a component about the direction of travel. In the case of a cricket ball the subtle behaviour of so-called ‘drift’, particularly ‘late drift’, and also ‘dip’, which may be produced by a slow bowler's off or leg-spin, are investigated. It is found that the trajectories obtained are broadly in accord with those observed in practice. We envisage that this paper may be useful in two ways: (i) for its inherent scientific value as, to the best of our knowledge, the fundamental equations derived here have not appeared in the literature and (ii) in cultivating student interest in the numerical solution of differential equations, since so many of them actively participate in ball-games, and they will be able to compare their own practical experience with the overall trends indicated by the numerical results. As the paper presents equations which can be further extended, it may be of interest to research workers. However, since only the most basic principles of fundamental mechanics are employed, it should be well within the grasp of first

  5. Single and multiple impact ignition of new and aged high explosives in the Steven Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; DePiero, A H; Garza, R G; Tarver, C M

    1999-06-01

    Threshold impact velocities for ignition of exothermic reaction were determined for several new and aged HMX-based solid high explosives using three types of projectiles in the Steven Test. Multiple impact threshold velocities were found to be approximately 10% lower in damaged charges that did not react in one or more prior impacts. Projectiles with protrusions that concentrate the friction work in a small volume of explosive reduced the threshold velocities by approximately 30%. Flat projectiles required nearly twice as high velocities for ignition as rounded projectiles. Blast overpressure gauges were used for both pristine and damaged charges to quantitatively measure reaction violence. Reactive flow calculations of single and multiple impacts with various projectiles suggest that the ignition rates double in damaged charges.

  6. Single and multiple impact ignition of new and aged high explosives in the Steven Impact Test

    International Nuclear Information System (INIS)

    Threshold impact velocities for ignition of exothermic reaction were determined for several new and aged HMX-based solid high explosives using three types of projectiles in the Steven Test. Multiple impact threshold velocities were found to be approximately 10% lower in damaged charges that did not react in one or more prior impacts. Projectiles with protrusions that concentrate the friction work in a small volume of explosive reduced the threshold velocities by approximately 30%. Flat projectiles required nearly twice as high velocities for ignition as rounded projectiles. Blast overpressure gauges were used for both pristine and damaged charges to quantitatively measure reaction violence. Reactive flow calculations of single and multiple impacts with various projectiles suggest that the ignition rates double in damaged charges

  7. Inner-shell ionization of heavy atoms by slow ions. A study of electronic relativistic effects and projectile Coulomb deflection in the Semiclassical Approximation

    International Nuclear Information System (INIS)

    Several investigations have been made on K and L shell ionization of the heavy collision partner in slow asymmetric collisions based on the SCA. The use of the SCA can only be defended for slow collisions if the projectile has a charge much less than the target. Thus this approximation should first be tested for proton impact on very heavy target elements. For these elements the inner shell electrons move sufficiently fast for a relativistic description to be mandatory. These relativistic effects are in themselves of some interest, as they can be quite large. After discussion of the formulation of the SCA used throughout this work, a further introduction is given on relativistic effects in Coulomb ionisation. Two papers on electronic relativistic effects in K and L shell ionization follow. The next two papers discuss calculations with an exact Coulomb projectile path. The latter of these also touches upon the inclusion of corrections to the SCA from terms beyond first order perturbation theory. In the last paper of this thesis it is shown how the theoretical apparatus developed for the SCA- calculations can immediately be used also for making calculations of more symmetric systems with the Briggs model. Thus, at least for direct ionization in very slow collisions a unification of the SA and MO approaches has apparently been reached. (JIW)

  8. An Example For The Effect of 5E Model on The Academic Success and Attitude of Students: “Projectile Motion”

    Directory of Open Access Journals (Sweden)

    İsmet ERGİN

    2006-12-01

    Full Text Available In this research; during the Physics Education course in GATA Medical Noncommissioned Officer Preparatory School’s first grade, Projectile Motion has been applied to the students with the fundamental principles of 5E Model and the effectiveness of the Physics Education course on academic success and attitudes of the students has been searched. Morever, after presenting the outcomes, some suggestions have been presented. While chosing the course subject, since, the students to whom the course subject has been applied are cadets, Projectile Motion subjects are chosen since they are both complex and interesting. The researh has been carried out with 84 students who were in GATA Medical Noncommissioned Officer Preparatory School’s First Grade. In the researh, multiple choicesuccess tests have been applied for each subject. In the analysis made after the application, It has been observed that the experiment group students to when the 5E Model has been applied react much more beneficial attitudes and are more successful than the control group students to whom the tradetional teaching method has been applied. Some suggestions have been presented by the help of the outcomes that were gained after the researh.

  9. Techniques for Surface-Temperature Measurements and Transition Detection on Projectiles at Hypersonic Velocities--Status Report No. 2

    Science.gov (United States)

    Bogdanoff, D. W.; Wilder, M. C.

    2006-01-01

    The latest developments in a research effort to advance techniques for measuring surface temperatures and heat fluxes and determining transition locations on projectiles in hypersonic free flight in a ballistic range are described. Spherical and hemispherical titanium projectiles were launched at muzzle velocities of 4.6-5.8 km/sec into air and nitrogen at pressures of 95-380 Torr. Hemisphere models with diameters of 2.22 cm had maximum pitch and yaw angles of 5.5-8 degrees and 4.7-7 degrees, depending on whether they were launched using an evacuated launch tube or not. Hemisphere models with diameters of 2.86 cm had maximum pitch and yaw angles of 2.0-2.5 degrees. Three intensified-charge-coupled-device (ICCD) cameras with wavelength sensitivity ranges of 480-870 nm (as well as one infrared camera with a wavelength sensitivity range of 3 to 5 microns), were used to obtain images of the projectiles in flight. Helium plumes were used to remove the radiating gas cap around the projectiles at the locations where ICCD camera images were taken. ICCD and infrared (IR) camera images of titanium hemisphere projectiles at velocities of 4.0-4.4 km/sec are presented as well as preliminary temperature data for these projectiles. Comparisons were made of normalized temperature data for shots at approx.190 Torr in air and nitrogen and with and without the launch tube evacuated. Shots into nitrogen had temperatures 6% lower than those into air. Evacuation of the launch tube was also found to lower the projectile temperatures by approx.6%.

  10. Research on Debris Transport Character in Penetrating Channel under Multi-projectiles Repetitive Explosion%多弹重复爆炸下侵彻通道内碎屑运移特性研究

    Institute of Scientific and Technical Information of China (English)

    刘彩花; 焦国太; 韩晶; 张世豪

    2014-01-01

    为了增加钻地武器的侵彻深度,提出一种“串联式”多弹连续爆炸作用方式。在单发弹静爆试验的基础上,拟合出多弹爆炸的周期性爆炸荷载曲线。通过FLUENT软件与EDEM软件耦合数值模拟可知,侵彻通道深度1m时周期性爆炸荷载作用下碎屑的运移能力得到增强,同时进一步研究了介质碎屑运移特性的影响因素。仿真结果表明:介质碎屑的运移能力与爆炸荷载峰值成正比,与碎屑粒径及弹体偏离钻地通道轴线距离成反比。%In order to increase the penetration depth of weapons,a new scheme of tandem multi-projectile contin-uous explosion was put forward. Based on static explosion test of single projectile,the periodical explosion load curve of multi-projectile explosion was also fitted. Through the coupling numerical simulation by the software FLUENT with EDEM,within 1m deep penetrating channels,the debris transport capability was enhanced under continuous explo-sion load. In addition,the influence factors of debris transport character was discussed. Results showed that debris transport capability was proportional to the peak value of explosion load,and inversely proportional to debris particle size and the offset distance of projectile and penetrating channel.

  11. Four-body charge transfer processes in collisions of bare projectile ions with helium atoms

    Science.gov (United States)

    Jana, S.; Mandal, C. R.; Purkait, M.

    2015-02-01

    Single-electron capture by a bare ion from a helium atom at intermediate and high energies in the framework of four-body distorted wave (DW-4B) approximation in both prior and post form has been considered. In the entrance channel, the initial bound state wave function is distorted by the incoming projectile ion, and the corresponding distortion is related to the Coulomb continuum states of the active electron and the residual target ion in the field of the projectile ion respectively. Continuum states of the active electron and the projectile ion in the field of the residual target ion are also included in the exit channel. It may be mentioned that the effect of dynamic electron correlation is explicitly taken into account through the complete perturbation potential. The total single-electron capture cross sections are obtained by summing over all contributions up to n = 3 shells and sub-shells respectively. In addition, the differential cross sections for alpha particle-helium collision are calculated at impact energies of 60, 150, 300, 450, and 630 keV amu-1, respectively. The cross sections exhibit a monotonically decreasing angular dependence, with clear peak structures around 0.1 to 0.2 mrad being found at low impact energies. The current theoretical results, both in prior and post forms of the transition amplitude for symmetric and asymmetric collision, are compared with the available theoretical and experimental results. Current computed results have been found to be satisfactory in comparison with other theoretical and experimental findings.

  12. Exact second Born calculations for electron capture for systems with various projectile and target charges

    International Nuclear Information System (INIS)

    Results of exact numerical calculations of differential and total 1s-1s electron-capture cross sections evaluated in the second Born approximation are presented for targets and projectiles of various charges Z/sub T/ and Z/sub P/ at velocities between 10 and 200 MeV/amu. For symmetric systems with Z/sub P/ = Z/sub T/ = Z the Thomas peak in the differential cross section, characteristic of a free-wave second Born-approximation process, appears at velocities above Z2 x (5 MeV/amu), where Z is the nuclear charge of the target (or projectile). The shape of this Thomas peak contains information about real and virtual intermediate states of the system. For total cross sections at velocities below Z2 x (2 MeV) the second Born-approximation cross section is larger than the first Born-approximation cross section indicating a breakdown of the second Born approximation using the free-wave Green's function. Results using the peaking approximation of Drisko converge to our exact second Born-approximation results only at velocities well above Z2 x (10 MeV/amu). For systems asymmetric in Z/sub P/ and Z/sub T/ no exact scaling is found, although the systematics are qualitatively similar to the symmetric case using Z = 1/2(Z/sub P/+Z/sub T/). For p+Ne at 100 MeV, the exact Born-approximation results lie somewhat above exact impulse-approximation calculations. It is found that the peaking approximation of Briggs and Simony converges to exact second Born-approximation results as the asymmetry of the projectile and target charges increases

  13. Four-body charge transfer processes in collisions of bare projectile ions with helium atoms

    International Nuclear Information System (INIS)

    Single-electron capture by a bare ion from a helium atom at intermediate and high energies in the framework of four-body distorted wave (DW-4B) approximation in both prior and post form has been considered. In the entrance channel, the initial bound state wave function is distorted by the incoming projectile ion, and the corresponding distortion is related to the Coulomb continuum states of the active electron and the residual target ion in the field of the projectile ion respectively. Continuum states of the active electron and the projectile ion in the field of the residual target ion are also included in the exit channel. It may be mentioned that the effect of dynamic electron correlation is explicitly taken into account through the complete perturbation potential. The total single-electron capture cross sections are obtained by summing over all contributions up to n = 3 shells and sub-shells respectively. In addition, the differential cross sections for alpha particle–helium collision are calculated at impact energies of 60, 150, 300, 450, and 630 keV amu−1, respectively. The cross sections exhibit a monotonically decreasing angular dependence, with clear peak structures around 0.1 to 0.2 mrad being found at low impact energies. The current theoretical results, both in prior and post forms of the transition amplitude for symmetric and asymmetric collision, are compared with the available theoretical and experimental results. Current computed results have been found to be satisfactory in comparison with other theoretical and experimental findings. (paper)

  14. Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes

    Science.gov (United States)

    Thies, R.; Heinz, A.; Adachi, T.; Aksyutina, Y.; Alcantara-Núñes, J.; Altstadt, S.; Alvarez-Pol, H.; Ashwood, N.; Aumann, T.; Avdeichikov, V.; Barr, M.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boretzky, K.; Borge, M. J. G.; Burgunder, G.; Camaño, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkäll, J.; Chakraborty, S.; Chartier, M.; Chulkov, L. V.; Cortina-Gil, D.; Crespo, R.; Datta, U.; Díaz Fernández, P.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estradé, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Freudenberger, M.; Fynbo, H. O. U.; Galaviz, D.; Geissel, H.; Gernhäuser, R.; Göbel, K.; Golubev, P.; Gonzalez Diaz, D.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Henriques, A.; Holl, M.; Ickert, G.; Ignatov, A.; Jakobsson, B.; Johansson, H. T.; Jonson, B.; Kalantar-Nayestanaki, N.; Kanungo, R.; Knöbel, R.; Kröll, T.; Krücken, R.; Kurcewicz, J.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lepyoshkina, O.; Lindberg, S.; Machado, J.; Marganiec, J.; Maroussov, V.; Mostazo, M.; Movsesyan, A.; Najafi, A.; Nilsson, T.; Nociforo, C.; Panin, V.; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Prochazka, A.; Rahaman, A.; Rastrepina, G.; Reifarth, R.; Ribeiro, G.; Ricciardi, M. V.; Rigollet, C.; Riisager, K.; Röder, M.; Rossi, D.; Sanchez del Rio, J.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Stoica, V.; Streicher, B.; Taylor, J. T.; Tengblad, O.; Terashima, S.; Togano, Y.; Uberseder, E.; Van de Walle, J.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Weigand, M.; Wheldon, C.; Wilson, G.; Wimmer, C.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M. V.; Zilges, A.; Zuber, K.; R3B Collaboration

    2016-05-01

    Background: Models describing nuclear fragmentation and fragmentation fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool for reaching the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from 10,12 -18C and B-1510 isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent data set. We compare our data to model calculations. Results: One-proton removal cross sections with different final neutron numbers (1 p x n ) for relativistic 10,12 -18C and B-1510 isotopes impinging on a carbon target. Comparing model calculations to the data, we find that the epax code is not able to describe the data satisfactorily. Using abrabla07 on the other hand, we find that the average excitation energy per abraded nucleon needs to be decreased from 27 MeV to 8.1 MeV. With that decrease abrabla07 describes the data surprisingly well. Conclusions: Extending the available data towards light unstable nuclei with a consistent set of new data has allowed a systematic investigation of the role of the excitation energy induced in projectile fragmentation. Most striking is the apparent mass dependence of the average excitation energy per abraded nucleon. Nevertheless, this parameter, which has been related to final-state interactions, requires further study.

  15. Self-Healing of Thermoplastic Poly(Ethylene-co-Methacrylic Acid) Copolymers Following Projectile Puncture

    OpenAIRE

    Kalista, Jr., Stephen James

    2003-01-01

    Poly(ethylene-co-methacrylic acid) (EMAA) ionomer polymers carry great potential for use in a wide variety of unique applications due to their property of "self-healing" following projectile impact. Following puncture, certain films based on these materials are observed to "heal", with the penetration opening recovering to an air-tight condition. Specifically, four polymers of this class were examined, including DuPont⠢ Surlyn® 8920, Surlyn® 8940, Nucrel® 925, and Nucrel® 960. Though ...

  16. Nuclear Matter Incompressibility Effect on the Cross Section of Fusion Reactions with a weakly bound projectile

    CERN Document Server

    Seyyedi, S A

    2015-01-01

    Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility effects, the fusion reaction cross sections and suppression parameters are calculated for 9Be +209Bi,208Pb,29Si and 27Al reactions. The results show that applying these effects at energies near the Coulomb barrier improves the agreement between the calculated and experimental cross sections, and modifies the mean values of the suppression parameter.

  17. Dynamical electron-electron correlation in C2+ + He simultaneous target-projectile collisional ionization

    International Nuclear Information System (INIS)

    Simultaneous target and projectile single ionization in 3.6 MeV u-1 C2+ + He collisions is considered, within a six-body classical trajectory Monte Carlo model. Analysis of the relative azimuthal angle between the two emitted electrons allows one to discriminate the ionization contribution produced by the two-centre dynamical electron-electron interaction from that due to nucleus-electron interactions. The present calculations agree well with cross section measurements recently performed in kinematically complete experiments. (letter to the editor)

  18. Accumulation of color centers in lithium fluoride crystals under irradiation with swift lead projectiles

    International Nuclear Information System (INIS)

    Lithium fluoride crystals were irradiated with lead ions of different energies, having the electronic energy loss of 10–20 keV/nm. Accumulation of F centers with fluence was studied by absorption UV–VIS spectroscopy. It was found that the average F-center concentration is mainly determined by the average absorbed energy density with a weak decrease above 1023 eV/cm3. A defect accumulation model, taking into account the recombination processes, is proposed for a seamless description of the F-center concentration fluence dependences for various projectiles and energy losses

  19. Accumulation of color centers in lithium fluoride crystals under irradiation with swift lead projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Benhacine, H. [LRPCSI, University of 20 Août 1955 Skikda, Route El-Hadaeik, 21000 Skikda (Algeria); Département de physique Université Constantine 1, Route Ain El-Bey 25000 (Algeria); Sorokin, M.V., E-mail: m40@lab2.ru [National Research Centre ‘Kurchatov Institute’, Kurchatov Square 1, 123182 Moscow (Russian Federation); Schwartz, K. [GSI Helmholtzzentrum für Schwerionenforschung, Planckstr. 1, 64291 Darmstadt (Germany); Meftah, A. [LRPCSI, University of 20 Août 1955 Skikda, Route El-Hadaeik, 21000 Skikda (Algeria)

    2015-09-15

    Lithium fluoride crystals were irradiated with lead ions of different energies, having the electronic energy loss of 10–20 keV/nm. Accumulation of F centers with fluence was studied by absorption UV–VIS spectroscopy. It was found that the average F-center concentration is mainly determined by the average absorbed energy density with a weak decrease above 10{sup 23} eV/cm{sup 3}. A defect accumulation model, taking into account the recombination processes, is proposed for a seamless description of the F-center concentration fluence dependences for various projectiles and energy losses.

  20. Maximum range of a projectile launched from a height h: a non-calculus treatment

    International Nuclear Information System (INIS)

    The classical example of problem solving, maximizing the range of a projectile launched from height h with velocity v over the ground level, has received various solutions. In some of these, one can find the maximization of the range R by differentiating R as a function of an independent variable or through the implicit differentiation in Cartesian or polar coordinates. In other papers, various elegant non-calculus solutions can be found. In this paper, this problem is revisited on the basis of the elementary analytical geometry and the trigonometry only. (papers)

  1. Present analytical possibilities in prompt γ-ray spectrometry with charged projectiles

    International Nuclear Information System (INIS)

    This review article deals with γ-rays following bombardment by charged projectiles and the use of this process as an analytical method. A general enumeration of analytical possibilities with expected sensitivities is given. The basic principles and the different possible productions are summarized. A discussion of the physical background is included. Methods for quantitative analysis are discussed. Experimental arrangements are indicated and factors affecting the accuracy of analysis are considered. A number of applications are briefly described and a comparison with X-ray emission (PIXE) is made

  2. Extrapolation of neutron-rich isotope cross-sections from projectile fragmentation

    OpenAIRE

    Mocko, M.; Tsang, M. B.; Z.Y. Sun; Andronenko, L.; Andronenko, M.; Delaunay, F.; Famiano, M.; Friedman, W. A.; Henzl, V.; Henzlova, D.; Hui, H.; Liu, X. D.; Lukyanov, S.; Lynch, W.G.; Rogers, A. M.

    2007-01-01

    Using the measured fragmentation cross sections produced from the 48Ca and 64Ni beams at 140 MeV per nucleon on 9Be and 181Ta targets, we find that the cross sections of unmeasured neutron rich nuclei can be extrapolated using a systematic trend involving the average binding energy. The extrapolated cross-sections will be very useful in planning experiments with neutron rich isotopes produced from projectile fragmentation. The proposed method is general and could be applied to other fragmenta...

  3. Numerical-analytical Algorithm for Constructing the Envelope of the Projectile Trajectories in Midair

    CERN Document Server

    Chudinov, Peter S

    2009-01-01

    A classic problem of the motion of a point mass (projectile) thrown at an angle to the horizon is reviewed. The air drag force is taken into account with the drag factor assumed to be constant. An analytic approach is mainly used for the investigation. Simple analytical formulas are used for the constructing the envelope of the family of the point mass trajectories. The equation of envelope is applied for the determination of the maximum range of flight. The motion of a baseball is presented as an example.

  4. Projectile X-ray emission in relativistic ion-atom collisions

    OpenAIRE

    Salem, Shadi

    2010-01-01

    This work reports on the study of the projectile x-ray emission in relativistic ion-atom collisions. Excitation of K-shell in He-like uranium ions, electron capture into H-like uranium ions and Simultaneous ionization and excitation of initially He-like uranium ions have been studied using the experimental storage ring at GSI. Information about the population of the excited states for the H- and He-like uranium ions, can be obtained by measuring the angular distribution of the decay radiation...

  5. Ablation modeling of electro-magnetically launched projectile for access to space

    Science.gov (United States)

    Gosse, Ryan C.

    It has been proposed to study and identify the technical issues involved in the launch to space of micro-satellite payloads using an airborne electromagnetic launcher (AEML). A computational fluid dynamics (CFD) computer code was developed to help characterize the aerothermal issues involved with the flight of the projectile as it exits the Earth's atmosphere. Conceptual geometries were chosen to evaluate the feasibility of launching to orbit from an aircraft. Due to expected high heating fluxes, carboncarbon material was selected for the thermal protection system (TPS). Results of the conceptual study are presented and used to evaluate the practicality of the AEML concept.

  6. Computerized System for Evaluating Small Arm Projectile Trajectory Parameters Involving Space Time Functions

    Directory of Open Access Journals (Sweden)

    M. Jauhari

    1982-07-01

    Full Text Available Evaluation of certain parameters of the trajectory of a small arm projectile on the basis of Siacci approximation requires the values of space (S and Time (T functions as tabulated in the Ingalls and Hodsock ballistic tables. The development is reported of a computerized system, whereby the necessity of referring to these tables has been completely obviated. Programme flow-char has been presented and the logic behind the flow of programme has been made explicit. The programme has been executed successfully on the DCM Microsystem 1121.

  7. Some physical magnitudes of interest for nuclear reactions and their dependence on the projectile-target system

    International Nuclear Information System (INIS)

    The design and analysis of experiences with heavy ions requires the knwoledge of several characteristic parameters of the collision and their dependence on the reactant system. In the case of an electrostatic accelerator as the TANDAR, the bombarding energy (function of the projectile) is a direct consequence of the evolution of the charged state distribution for the projectile at the exit of the last stripper, as a function of the atomic number. The complexity resulting from this dependence originated the confection of a series of diagrams. The diagrams correpond to the different physical magnitudes of interest in the analysis of nuclear reactions as a function of the projectile-target combination for terminal tensions similar to those expected to reach at the TANDAR. In each case, the curves are refered to the following physical magnitudes: Ecm/Bc Kinetic energy in the center of the mass system and Coulomb barrier for the projectile-target system, Lgr = angular momentum corresponding to the grazing collisions. Diagrams of the average projectile energy per nucleon for the different values of the terminal tensions with one or two solid strippers are included. The use of the diagrams in some practical applications is illustrated through four examples. The diagrams may be extended, if necesary, to other physical magnitudes, at different accelerator's operating conditions. (M.E.L.)

  8. Fusion with projectiles form carbon to argon at energies between 20A and 60A MeV

    International Nuclear Information System (INIS)

    A review of the linear momentum transfer is made, considering essentially heavy targets and two important parameters in the entrance channel: the projectile energy and its mass. Over a broad mass range, and for energies up to 30A MeV, the momentum transfer scales with the mass of the projectile. At 30A MeV, the most probable value of projectile momentum transferred to the fused system is 80%, and this represents roughly 180 MEV/c per projectile nucleon. At higher bombarding energies, the momentum distribution in the fused systems, as observed from binary fission events, seems to depend on the mass of the projectile. Further studies are still needed to understand this behaviour. Finally, the decay of highly excited (E* approximately 500-800 MeV) fused systems, with masses close to 270 amu, is studied from the characteristics of both fusion fragments and light charged particles. It is shown that thermal equilibrium is reached before fission, even for such high energy deposition. However, the decay sequence is sensitive to dynamical effects and does not depend only on available phase space

  9. Sputtering of Langmuir-Blodgett multilayers by keV C60 projectiles as seen by computer simulations

    International Nuclear Information System (INIS)

    Fundamental processes induced in a thick organic system composed of long, well-organized linear molecules by an impact of 5-20 keV C60 are investigated. The organic system is represented by Langmuir-Blodgett multilayers formed from bariated molecules of arachidic acid. The thickness of the system varies between 2 and 16 nm. Coarse-grained molecular dynamics computer simulations are applied to investigate the energy transfer pathways and sputtering yields as a function of the kinetic energy of the projectile and the thickness of the organic overlayer. The results indicate that an impact of keV C60 projectiles leads to significant ejection of organic material. The efficiency of desorption increases with the kinetic energy of the projectile for a given layer thickness. For a constant primary kinetic energy, the sputtering yield goes through a maximum and finally saturates as the LB layer becomes thicker. Such behaviour is caused by a competition between signal enhancement due to increasing number of organic molecules and signal decrease due to lowering of the amount of the primary energy being backreflected into the organic overlayer by the receding organic/metal interface as the layer is getting thicker. When the sample thickness becomes much larger than the penetration depth of the projectile, the sputtering yield is independent of thickness. The deposited energy is channelled by an open and ordered molecular structure, which leads to abnormally long projectile penetration and ion-induced damage.

  10. Sputtering of Langmuir-Blodgett multilayers by keV C{sub 60} projectiles as seen by computer simulations

    Energy Technology Data Exchange (ETDEWEB)

    Paruch, R.; Rzeznik, L.; Czerwinski, B. [Smoluchowski Institute of Physics, Jagiellonian University, ul. Reymonta 4, 30-059 Krakow (Poland); Garrison, B.J.; Winograd, N. [Department of Chemistry, Pennsylvania State University, University Park, PA 16802 (United States); Postawa, Z. [Smoluchowski Institute of Physics, Jagiellonian University, ul. Reymonta 4, 30-059 Krakow (Poland)], E-mail: zp@castor.if.uj.edu.pl

    2009-08-15

    Fundamental processes induced in a thick organic system composed of long, well-organized linear molecules by an impact of 5-20 keV C{sub 60} are investigated. The organic system is represented by Langmuir-Blodgett multilayers formed from bariated molecules of arachidic acid. The thickness of the system varies between 2 and 16 nm. Coarse-grained molecular dynamics computer simulations are applied to investigate the energy transfer pathways and sputtering yields as a function of the kinetic energy of the projectile and the thickness of the organic overlayer. The results indicate that an impact of keV C{sub 60} projectiles leads to significant ejection of organic material. The efficiency of desorption increases with the kinetic energy of the projectile for a given layer thickness. For a constant primary kinetic energy, the sputtering yield goes through a maximum and finally saturates as the LB layer becomes thicker. Such behaviour is caused by a competition between signal enhancement due to increasing number of organic molecules and signal decrease due to lowering of the amount of the primary energy being backreflected into the organic overlayer by the receding organic/metal interface as the layer is getting thicker. When the sample thickness becomes much larger than the penetration depth of the projectile, the sputtering yield is independent of thickness. The deposited energy is channelled by an open and ordered molecular structure, which leads to abnormally long projectile penetration and ion-induced damage.

  11. Application des techniques de contrôle des écoulements au pilotage des projectiles : Contrôle fluidique d'un projectile gyrostabilisé de 155 mm par effet Coanda

    OpenAIRE

    Zeidler, M

    2015-01-01

    Afin d'améliorer les performances des systèmes d'armes, les industriels de l'armement envisagent la mise en service de projectiles intégrant une capacité de correction de trajectoires. Le principal objectif consiste à proposer de nouveaux dispositifs de correction permettant de réduire l'erreur de dispersion de l'engin. Dans le cadre de projectiles aérostabilisés, le contrôle de leurs trajectoires est assuré à l'aide de surfaces portantes, technologie éprouvée depuis de nombreuses décennies. ...

  12. Determination of 2> from fission fragment anisotropy for reactions involving weakly bound 6,7Li projectiles

    International Nuclear Information System (INIS)

    Fission fragment (FF) angular distributions for 6,7Li+235,238U reactions and FF mass distributions for 6,7Li+238U reactions have been measured at energies around the Coulomb barrier and reported in earlier symposia. The aim is to investigate the effect of projectile breakup on various observables in fission reactions. Due to low breakup threshold there is a probability of breakup of the projectiles which in turn may affect the compound nucleus (CN) formation cross section. In the present study it is proposed to determine the 2 > from the measured fission fragment anisotropy and compare them with the ones obtained from coupled channels calculations to investigate the effect of projectile breakup

  13. Experimental and theoretical results on electron emission in collisions between He targets and dressed Liq+ (q = 1, 2) projectiles

    International Nuclear Information System (INIS)

    We investigate experimentally and theoretically the electron emission in collisions between He atoms and Liq+ (q = 1, 2) projectiles at intermediate to high incident energies. We report on measured absolute values of double-differential cross-sections, as a function of the emitted electron energy and angle, at a collision energy of 440 keV u−1. The different contributions from target ionization, projectile ionization, and simultaneous target–projectile ionization are calculated with the quantum-mechanical continuum distorted wave and continuum distorted wave–eikonal initial state models, and with classical trajectory Monte Carlo simulations. There is an overall good agreement of the calculations with the experimental data for electron emission cross-sections. (paper)

  14. Absolute cross sections for projectile electron loss accompanied by target multiple ionization in collisions of He+ with noble gases

    Science.gov (United States)

    Santos, A. C. F.; Sigaud, G. M.; Melo, W. S.; Sant'Anna, M. M.; Montenegro, E. C.

    2011-02-01

    Absolute cross sections for projectile electron loss accompanied by target multiple ionization in collisions between He+ ions and noble gases have been measured for energies between 1.0 and 3.5 MeV. The data have been compared with other absolute cross sections that exist in the literature for the same projectile, and with calculations for the screening mode (nucleus-electron interaction) using both perturbative (plane-wave Born approximation (PWBA)) and non-perturbative (extended classical-impulse free-collision model, sudden approximation and coupled-channel method) approaches, and for the antiscreening mode (electron-electron interaction) within the PWBA. The energy dependence of the average number of active electrons for the antiscreening has been described by means of a simple function, which is 'universal' for noble gases but projectile dependent. A previously developed method has been employed to obtain the number of active electrons for each target subshell in the high-velocity regime.

  15. Absolute cross sections for projectile electron loss accompanied by target multiple ionization in collisions of He+ with noble gases

    International Nuclear Information System (INIS)

    Absolute cross sections for projectile electron loss accompanied by target multiple ionization in collisions between He+ ions and noble gases have been measured for energies between 1.0 and 3.5 MeV. The data have been compared with other absolute cross sections that exist in the literature for the same projectile, and with calculations for the screening mode (nucleus-electron interaction) using both perturbative (plane-wave Born approximation (PWBA)) and non-perturbative (extended classical-impulse free-collision model, sudden approximation and coupled-channel method) approaches, and for the antiscreening mode (electron-electron interaction) within the PWBA. The energy dependence of the average number of active electrons for the antiscreening has been described by means of a simple function, which is 'universal' for noble gases but projectile dependent. A previously developed method has been employed to obtain the number of active electrons for each target subshell in the high-velocity regime.

  16. High resolution measurements of heavy residues from 197Au projectile fragmentation at 20 MeV/u

    International Nuclear Information System (INIS)

    The yields and momentum distributions of heavy residues from the fragmentation of 197Au projectiles at 20MeV/nucleon by C, Al and Ti targets have been measured at 0 degrees. Projectile residues (and fission fragments) were analyzed using the A1200 mass separator at the NSCL and stopped in a Si-detector telescope placed at the focal plane of the separator. The nuclear charge, ionic charge, mass and momentum of the residues were deduced. The analysis of the data has shown that unit Z and A resolution is obtained for a broad range of reaction products, from near-projectile residues to fission fragments. The residue properties at this energy show a target dependence, in contrast to available data at higher energies. The momentum distributions indicate that incomplete and complete fusion (accompanied by fission or particle emission) and fragmentation are the main mechanisms contributing to the production of the residues at this energy regime

  17. Evaluation of the performance of three elastomers for non-lethal projectile applications

    Science.gov (United States)

    Thota, N.; Epaarachchi, J.; Lau, K. T.

    2015-09-01

    Less lethal kinetic ammunitions with soft noses such as eXact iMpact 1006, National Sports Spartan and B&T have been commonly used by military and law enforcement officers in the situations where lethal force is not warranted. In order to explore new materials to be used as nose in such ammunitions, a scholastic study using finite element simulations has been carried out to evaluate the effectiveness of two rubber like elastomers and a polyolefinic foam (low density, highly compressible, stiff and closed cell type of thermos plastic elastomer). State-of-the art thorax surrogate MTHOTA has been employed for the evaluation of blunt thoracic trauma. Force-rigid wall method was employed for the evaluation of head damage curves for each material. XM 1006 has been used as the benchmark projectile for the purpose of comparison. Both blunt thoracic trauma and head damage criterion point of view, both rubbers (R1 and R2) have yielded high values of VCmax and peak impact force. Polyolefinic foam (F1) considered in the study has yielded very promising VCmax values and very less peak impact force when compared with those of bench mark projectile XM 1006.

  18. Prospects for the discovery of the next new element: Influence of projectiles with Z > 20

    CERN Document Server

    Folden, Charles M; Werke, Tyler A; Alfonso, Marisa C; Bennett, Megan E; DeVanzo, Michael J

    2012-01-01

    The possibility of forming new superheavy elements with projectiles having Z > 20 is discussed. Current research has focused on the fusion of 48Ca with actinides targets, but these reactions cannot be used for new element discoveries in the future due to a lack of available target material. The influence on reaction cross sections of projectiles with Z > 20 have been studied in so-called analog reactions, which utilize lanthanide targets carefully chosen to create compound nuclei with energetics similar to those found in superheavy element production. The reactions 48Ca, 45Sc, 50Ti, 54Cr + 159Tb, 162Dy have been studied at the Cyclotron Institute at Texas A&M University using the Momentum Achromat Recoil Spectrometer. The results of these experimental studies are discussed in terms of the influence of collective enhancements to level density for compound nuclei near closed shells, and the implications for the production of superheavy elements. We have observed no evidence to contradict theoretical predict...

  19. Lithic raw material procurement for projectiles points in the prehistory of Uruguay

    Directory of Open Access Journals (Sweden)

    José María López Mazz

    2015-03-01

    Full Text Available This paper focuses on current research on early colonisation of the Atlantic coast of South America during the early Holocene. We present advances in the investigation of raw material procurement at the Rincón de los Indios site, located in the eastern part of Uruguay. The technological studies suggest that some aspects of different styles of projectile points are related with environmental adaptation processes, experienced by the first American people in the New World. The occupation of new spaces and new forms of exploitation of resources changes the organisation of lithic technology. The distance to good quality rocks were critical for the opportunities and economic organisation of hunting groups. The study of changes in lithic procurement strategies for projectile points helps us develop a more comprehensive knowledge of this important social adaptation process which occurred during this period. These patterns started to become stabilised in the latter part of the early Holocene across the extended territory and confirm the efficient land occupation associated an intensive hunter-gatherer economies.

  20. The influence of projectile ion induced chemistry on surface pattern formation

    Science.gov (United States)

    Karmakar, Prasanta; Satpati, Biswarup

    2016-07-01

    We report the critical role of projectile induced chemical inhomogeneity on surface nanostructure formation. Experimental inconsistency is common for low energy ion beam induced nanostructure formation in the presence of uncontrolled and complex contamination. To explore the precise role of contamination on such structure formation during low energy ion bombardment, a simple and clean experimental study is performed by selecting mono-element semiconductors as the target and chemically inert or reactive ion beams as the projectile as well as the source of controlled contamination. It is shown by Atomic Force Microscopy, Cross-sectional Transmission Electron Microscopy, and Electron Energy Loss Spectroscopy measurements that bombardment of nitrogen-like reactive ions on Silicon and Germanium surfaces forms a chemical compound at impact zones. Continuous bombardment of the same ions generates surface instability due to unequal sputtering and non-uniform re-arrangement of the elemental atom and compound. This instability leads to ripple formation during ion bombardment. For Argon-like chemically inert ion bombardment, the chemical inhomogeneity induced boost is absent; as a result, no ripples are observed in the same ion energy and fluence.

  1. A STUDY ON THE COUNTER-INTUITIVE BEHAVIORS OF PIN-ENDED BEAMS UNDER PROJECTILE IMPACT

    Institute of Scientific and Technical Information of China (English)

    Li Haiwang; Qin Dongqi

    2006-01-01

    The counter-intuitive behaviors of pin-ended beams under the projectile impact are investigated with ANSYS/LS-DYNA in this paper. It studies in detail their displacement-time history curves, final deformed shapes, energy relationships and projectile impact velocity ranges related to their counterintuitive behaviors. The influences of the impact positions on their counterintuitive behaviors are also discussed. The results show that no matter where the impact position on the beam is, the counter-intuitive behaviors of pinned beams will occur as long as the impacting velocity lies within a proper range. Corresponding to the occurring of the counterintuitive behaviors, the rebounding number in the displacement history curves of the beams decreases from a few times to zero with an increase of the impact velocity. The final deformation modes of the beam corresponding to the counter-intuitive behaviors will appear in symmetrical and unsymmetrical forms no matter where the impact position is; the impact velocity of the first-occurring of the counter-intuitive behaviors of the beam increases slowly with the deviation of the impact position away from the mid-span.

  2. Prospects for the discovery of the next new element: Influence of projectiles with Z > 20

    International Nuclear Information System (INIS)

    The possibility of forming new superheavy elements with projectiles having Z > 20 is discussed. Current research has focused on the fusion of 48Ca with actinide targets, but these reactions cannot be used for new element discoveries in the future due to a lack of available target material. The influence on reaction cross sections of projectiles with Z > 20 have been studied in so-called analog reactions, which utilize lanthanide targets carefully chosen to create compound nuclei with energetics similar to those found in superheavy element production. The reactions 48Ca, 45Sc, 50Ti, 54Cr + 159Tb, 162Dy have been studied at the Cyclotron Institute at Texas A and M University using the Momentum Achromat Recoil Spectrometer. The results of these experimental studies are discussed in terms of the influence of collective enhancements to level density for compound nuclei near closed shells, and the implications for the production of superheavy elements. We have observed no evidence to contradict theoretical predictions that the maximum cross section for the 249Cf(50Ti, 4n)295120 and 248Cm(54Cr, 4n)298120 reactions should be in the range of 10-100 fb.

  3. Electron capture by fully stripped high-Z projectiles from the hydrogen atom

    International Nuclear Information System (INIS)

    A single-channel distorted-wave approximation is used to calculate the one-electron capture cross section into an arbitrary state (nlm) of Ti22+, V23+, and Fe26+ from the ground state of a hydrogen atom. Since the interaction between the heavy projectile and the target electron is stronger, we represent the initial-channel wave function by a continuum distorted wave while the wave function in the final channel is taken to be a traveling atomic orbital. The nth partial cross sections are found to be in qualitative agreement with previous calculations for some other systems. It is found that at high energies the value nmax, where the nth partial cross section is maximum, is larger by a few steps than obtained from the nmax=Z3/4 model. However, for a fixed projectile nmax moves towards the smaller values as the energy increases. The l dependence of the cross sections are also studied at different energies at the corresponding nmax. We have further studied the mth partial cross sections at various energies and at the corresponding nmax for several l values. It is found that the contributions from higher m values are decreasing rapidly for m>5

  4. EFFECT OF BODY SHAPE ON THE AERODYNAMICS OF PROJECTILES AT SUPERSONIC SPEEDS

    Directory of Open Access Journals (Sweden)

    ABDULKAREEM SH. MAHDI

    2008-12-01

    Full Text Available An investigation has been made to predict the effects of forebody and afterbody shapes on the aerodynamic characteristics of several projectile bodies at supersonic speeds using analytical methods combined with semi-empirical design curves. The considered projectile bodies had a length-to-diameter ratio of 6.67 and included three variations of forebody shape and three variations of afterbody shape. The results, which are verified by comparison with available experimental data, indicated that the lowest drag was achieved with a cone-cylinder at the considered Mach number range. It is also shown that the drag can be reduced by boattailing the afterbody. The centre-of-pressure assumed a slightly rearward location for the ogive-cylinder configuration when compared to the configuration with boattailed afterbody where it was the most forward. With the exception of the boattailed afterbody, all the bodies indicated inherent static stability above Mach number 2 for a centre-of-gravity location at about 40% from the body nose.

  5. Evaluation of the performance of three elastomers for non-lethal projectile applications

    Directory of Open Access Journals (Sweden)

    Thota N.

    2015-01-01

    Full Text Available Less lethal kinetic ammunitions with soft noses such as eXact iMpact 1006, National Sports Spartan and B&T have been commonly used by military and law enforcement officers in the situations where lethal force is not warranted. In order to explore new materials to be used as nose in such ammunitions, a scholastic study using finite element simulations has been carried out to evaluate the effectiveness of two rubber like elastomers and a polyolefinic foam (low density, highly compressible, stiff and closed cell type of thermos plastic elastomer. State-of-the art thorax surrogate MTHOTA has been employed for the evaluation of blunt thoracic trauma. Force-rigid wall method was employed for the evaluation of head damage curves for each material. XM 1006 has been used as the benchmark projectile for the purpose of comparison. Both blunt thoracic trauma and head damage criterion point of view, both rubbers (R1 and R2 have yielded high values of VCmax and peak impact force. Polyolefinic foam (F1 considered in the study has yielded very promising VCmax values and very less peak impact force when compared with those of bench mark projectile XM 1006.

  6. Classical simulations of heavy-ion fusion reactions and weakly-bound projectile breakup reactions

    Indian Academy of Sciences (India)

    S S Godre

    2014-05-01

    Heavy-ion collision simulations in various classical models are discussed. Heavy-ion reactions with spherical and deformed nuclei are simulated in a classical rigid-body dynamics (CRBD) model which takes into account the reorientation of the deformed projectile. It is found that the barrier parameters depend not only on the initial orientations of the deformed nucleus, but also on the collision energy and the moment of inertia of the deformed nucleus. Maximum reorientation effect occurs at near- and below-barrier energies for light deformed nuclei. Calculated fusion crosssections for 24Mg + 208Pb reaction are compared with a static-barrier-penetration model (SBPM) calculation to see the effect of reorientation. Heavy-ion reactions are also simulated in a 3-stage classical molecular dynamics (3S-CMD) model in which the rigid-body constraints are relaxed when the two nuclei are close to the barrier thus, taking into account all the rotational and vibrational degrees of freedom in the same calculation. This model is extended to simulate heavy-ion reactions such as 6Li + 209Bi involving the weakly-bound projectile considered as a weakly-bound cluster of deuteron and 4He nuclei, thus, simulating a 3-body system in 3S-CMD model. All the essential features of breakup reactions, such as complete fusion, incomplete fusion, no-capture breakup and scattering are demonstrated.

  7. Grain to continuum considering mesoscale: computational framework for projectile penetration through granular material

    Science.gov (United States)

    Turner, Anne; Penumadu, Dayakar; Herbold, Eric

    2015-06-01

    High-speed projectile penetration through granular materials is governed by the particle or grain level (meso-scale) physics including inter-granular contact forces, particle reorientation, deformation and fragmentation. In this work, we investigate a method for numerically capturing the initial meso-structure of the assembly and morphology of individual particles using high resolution computed X-ray and neutron tomography. Using the finite element code, GEODYN-L, Ottawa sand specimen assembly directly measured from high resolution computed radiation based tomography non-invasively are numerically simulated to represent the initial state of compaction and subsequently subjected to one-dimensional compression. The effects of selected finite element formulations and grain discretization approaches are investigated to maximize the ability to capture high stress concentrations at contact points between grains, where fracture is likely to initiate, yet maintaining computational efficiency. The effect of coordination number on the contact forces and resulting stress distribution within a grain is also examined. This ``grain to continuum considering meso-scale'' computational framework is being developed to for realistic representation of deformation and damage mechanics associated with projectile penetration through granular materials. DTRA Grant HDTRA1-12-1-0045 managed by Dr. Suhiti Peiris.

  8. Effects of the projectile electronic structure on Bethe-Bloch stopping parameters for Ag

    Science.gov (United States)

    Moussa, D.; Damache, S.; Ouichaoui, S.

    2010-06-01

    Energy losses of protons and alpha particles in silver have been accurately measured under the same experimental conditions over the velocity range E=(0.192-2.595) MeV/amu using the transmission method. Deduced S(E) stopping powers are compared to most accurate ones from the literature, to values generated by the SRIM-2008 computer code and to ICRU-49 compilation. They were analyzed in the framework of modified Bethe-Bloch theory for extracting Ag target mean excitation and ionization potential, I, and Barkas effect parameter, b. Values of ( 466±5) eV and 1.20±0.01 for these two parameters were inferred from the proton S(E) data while the alpha particle data yielded values of (438±4) eV and 1.38±0.01, respectively. The ( I, b) stopping parameters thus exhibit opposite variations as the projectile charge increases, similarly as we have found previously for nickel [6]. This can be ascribed only to an effect of the projectile electronic structure at low velocities. The obtained results are discussed in comparison to previous ones reported in the literature.

  9. Effects of the projectile electronic structure on stopping parameters for nickel

    Science.gov (United States)

    Damache, S.; Ouichaoui, S.; Moussa, D.; Dib, A.

    2006-08-01

    The stopping powers of nickel foils for 1H+, 2H+ and 4He2+ ions have been accurately measured over the energy range E ≈ (0.166-2.725) MeV/amu. The data were compared to those reported in the literature and to values derived by the SRIM-2003 code. They were analysed in the framework of the modified Bethe-Bloch theory to extract the target mean excitation and ionisation potential, I, and the Barkas effect parameter, b. The values derived from the proton and the alpha particle data are {I = (311.11 ± 2.61) eV, b = 1.38 ± 0.01} and {I = (276.12 ± 2.84) eV, b = 1.58 ± 0.01}, respectively. They thus show opposite variations of the I and b parameters as the projectile charge increases, presumably due only to the incident ions electronic structure. Besides, the reduced stopping power data for incident deuterons show to be fully consistent with those for protons indicating no effect of the projectile isotopic structure on the target stopping parameters. These results are discussed in comparison with ones reported in the literature.

  10. Pressure moment on a liquid-filled projectile: Solid body rotation

    Science.gov (United States)

    Gerber, N.; Sedney, R.; Bartos, J. M.

    1982-10-01

    The liquid produced moment on a liquid filled spinning cylinder executing angular motion is determined, where the liquid originally is in solid body rotation. In an approximation to free flight spiraling motion of a projectile, the cylinder is nutating at constant frequency about a point on its axis and is undergoing timewise exponential yaw growth. The assumption of small yaw angle permits the formulation of a linearized viscous flow problem as a perturbation on solid body rotation. The pressure obtained from the resulting linearized flow is used to obtain the moment. Moment due to shear stresses is not considered. This moment is incorporated into the dynamical equations of gyroscopic motion to determine yaw growth rate and mutational frequency. This report provides a presentation of the equations and computational procedures. The approach is to apply a modal analysis in the flow solution which gives rise to ordinary differential equations, and then to make a correction required to compensate for neglect of the no slip conditions at the endwalls in the modal analysis. Results are compared with those of other theoretical work and with experimental data for endwall pressure, pressure moment, and yaw growth rate of projectiles and gyroscopes. In general, results agree well for high Reynolds number. Relative discrepancies are more prominent at low Reynolds numbers, particularly in yaw growth rate data. Qualitative agreement of present results with concurrent theoretical work of Murphy appears to be consistently good.

  11. Inhibited Shaped Charge Launcher Testing of Spacecraft Shield Designs

    Science.gov (United States)

    Grosch, Donald J.

    1996-01-01

    This report describes a test program in which several orbital debris shield designs were impact tested using the inhibited shaped charge launcher facility at Southwest Research Institute. This facility enables researchers to study the impact of one-gram aluminum projectiles on various shielding designs at velocities above 11 km/s. A total of twenty tests were conducted on targets provided by NASA-MSFC. This report discusses in detail the shield design, the projectile parameters and the test configuration used for each test. A brief discussion of the target damage is provided, as the detailed analysis of the target response will be done by NASA-MSFC.

  12. Design and validation of a fuzzy logic controller for a smart projectile fin with a piezoelectric macro-fiber composite bimorph actuator

    International Nuclear Information System (INIS)

    This paper focuses on the design and validation of a fuzzy logic controller for the smart fin of a projectile. The hollow fin is actuated by a cantilevered piezoelectric bimorph that is completely enclosed within it. A linear model of the actuator and fin is identified experimentally by exciting the system using a chirp signal. A procedure for designing a genetic algorithm (GA)-based fuzzy logic controller for the fin is presented. The controller is validated using simulation and experimental testing that is conducted in the subsonic wind tunnel at the University of Nevada, Las Vegas (UNLV). Results show that the proposed controller accomplishes the desired fin angle control under various operating conditions

  13. Novel method for the production of spin-aligned RI beams in projectile fragmentation reaction with the dispersion matching technique

    International Nuclear Information System (INIS)

    A novel method to produce spin-aligned rare-isotope (RI) beam has been developed, that is the two-step projectile fragmentation method with a technique of dispersion matching. The present method was verified in an experiment at the RIKEN RIBF, where an RI beam of 32Al with spin alignment of 8(1) % was successfully produced from a primary beam of 48Ca, with 33Al as an intermediate nucleus. Figure of merit of the present method was found to be improved by a factor larger than 50 compared with a conventional method employing single-step projectile fragmentation.

  14. New approach to the nuclear in beam {gamma} spectroscopy of neutron rich nuclei at N=20 using projectile fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Jimenez, M.J.; Saint-Laurent, M.G.; Achouri, L.; Daugas, J.M. [Grand Accelerateur National d`Ions Lourds, 14 - Caen (France); Belleguic, M.; Azaiez, F.; Bourgeois, C. [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire; Stanoiu, M.; Borcea, C. [Institute of Atomic Physics, Bucharest (Romania); Angelique, J.C. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire] [and others

    1999-11-01

    The structure of nuclei far from stability around {sup 32}Mg have been recently investigated by means of a novel method. In-beam {gamma}-decay spectroscopy of a large number of exotic neutron-rich nuclei produced by projectile fragmentation of a {sup 36}S projectile has been performed, using coincidences between the recoil fragments collected at the focal plane of SPEG spectrometer and {gamma}-rays emitted at the target location. Preliminary results on both the population mechanism and the decay of excited states in nuclei around {sup 32}Mg are presented. (author) 24 refs.

  15. Role of projectile charge state in convoy electron emission by fast protons colliding with LiF(0 0 1)

    Science.gov (United States)

    Aldazabal, I.; Gravielle, M. S.; Miraglia, J. E.; Arnau, A.; Ponce, V. H.

    2005-05-01

    Target ionization and projectile ionization differential cross sections are used to calculate the electron emission spectra by fast proton impact on ionic crystal surfaces under grazing incidence conditions. Both bare protons and neutral hydrogen species are considered. We use a planar potential approach to determine the projectile trajectory that later on allows us to calculate the charge state fractions. We show that, although the fraction of protons is significantly higher, the contribution from neutral hydrogen ionization has to be considered. The energy and angular dependence of the spectra is analyzed.

  16. Yaw and spin effects on high intensity sound generation and on drag of training projectiles with ring cavities

    Science.gov (United States)

    Parthasarathy, S. P.; Cho, Y. I.; Kwack, E. Y.; Back, L. H.

    1986-01-01

    Projectiles containing axisymmetric ring cavities constitute aeroacoustic sources. These produce high intensity tones which are used for coding in the SAWE (Simulation of Area Weapons Effects) system. Experimental data obtained in a free jet facility are presented describing the effects of yaw, spin and geometric projectile parameters on sound pressure and drag. In general, the sound pressure decreases with increasing yaw angle whereas the drag increases. Spin tends to increase sound pressure levels because of a reduction in asymmetry of flow. Drag increases at zero yaw approximately as the 1.5 power of sound wavelength. A significant part of the drag increase appears to be due to energy loss by sound radiation.

  17. Novel method for the production of spin-aligned RI beams in projectile fragmentation reaction with the dispersion matching technique

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, Y., E-mail: yuichikawa@phys.titech.ac.jp [Tokyo Institute of Technology, Department of Physics (Japan); Ueno, H. [RIKEN Nishina Center (Japan); Ishii, Y. [Tokyo Institute of Technology, Department of Physics (Japan); Furukawa, T. [Tokyo Metropolitan University, Department of Physics (Japan); Yoshimi, A. [Okayama University, Research Core for Extreme Quantum World (Japan); Kameda, D.; Watanabe, H.; Aoi, N. [RIKEN Nishina Center (Japan); Asahi, K. [Tokyo Institute of Technology, Department of Physics (Japan); Balabanski, D. L. [Bulgarian Academy of Sciences, Institute for Nuclear Research and Nuclear Energy (Bulgaria); Chevrier, R.; Daugas, J. M. [CEA, DAM, DIF (France); Fukuda, N. [RIKEN Nishina Center (Japan); Georgiev, G. [CSNSM, IN2P3-CNRS, Universite Paris-sud (France); Hayashi, H.; Iijima, H. [Tokyo Institute of Technology, Department of Physics (Japan); Inabe, N. [RIKEN Nishina Center (Japan); Inoue, T. [Tokyo Institute of Technology, Department of Physics (Japan); Ishihara, M.; Kubo, T. [RIKEN Nishina Center (Japan); and others

    2013-05-15

    A novel method to produce spin-aligned rare-isotope (RI) beam has been developed, that is the two-step projectile fragmentation method with a technique of dispersion matching. The present method was verified in an experiment at the RIKEN RIBF, where an RI beam of {sup 32}Al with spin alignment of 8(1) % was successfully produced from a primary beam of {sup 48}Ca, with {sup 33}Al as an intermediate nucleus. Figure of merit of the present method was found to be improved by a factor larger than 50 compared with a conventional method employing single-step projectile fragmentation.

  18. Study of the reaction mechanisms in the system20Ne + 197Au at projectile energies between 7.5 and 20 MeV/u

    International Nuclear Information System (INIS)

    In the present thesis the system 20Ne + 197Au was studied at projectile energies of 150, 220, 290 and 400 MeV. Energy and angular distributions of the projectile-like fragments, the light particles, and the fission fragments were measured. From the comparison of the fission cross section and the cross section of the projectile-like fragments it turned out that these two contributions supplement mutually to the reaction cross section which was determined by calculations by means of the optical model. Both contributions have to be assigned to mutually independent reaction types. In the second part the measured data are compared with different models (Qgg systematics, models for the optimal Q value, for projectile fragmentation and sequential emission of light particles). Thereby result following results: Evidence for the projectile fragmentation as it was described by Gelbke et al. (1977) couldn't be found, rather the sequential emission of light particles increasing with growing projectile energy. By this process at high energies about the half of the cross section of the 'fast', i.e. about with projectile velocity flying alpha particles can be explained. The other half must then result from the incomplete fusion of the projectile with the target which explains a part of the against theoretical expectations too large cross section. (orig./HSI)

  19. Study of the reaction mechanisms leading to projectile fragmentation in 40 Ar + Ag nat reactions at 30 MeV and 60 MeV per nucleon

    International Nuclear Information System (INIS)

    This work is devoted to a study of the reaction mechanisms leading to projectile fragmentation in heavy ion collisions at intermediate energy (less than 100 MeV per nucleon). In contradiction with some theoretical calculations, inclusive measurements of projectile fragments as well as correlation measurements between projectile and target fragments in the reaction 40Ar + natAg at 30 MeV and 60 MeV per nucleon do not show any evidence for a change in the reaction mechanism in this energy range. Angular, mass and velocity correlations between projectile and target fragments enable us to reject mass transfer from projectile to target as a leading mechanism in projectile fragmentations. However, a coherent description of the data can be given either in the framework of an abrasion-ablation model in which the primary fragments of the projectile and of the target are produced with very low excitation energies, or assuming a two-body reaction, reminiscent of the first steps of deeply inelastic collisions, in which the dissipated energy is shared about equally between strongly excited projectile and target. The high excitation energies deduced from the two-body analysis bring in question our description of the fragmentation process. Thus, the excitation energy of the primary fragment is a key parameter which may be used in future experiments to distinguish between different reaction mechanisms

  20. Test

    DEFF Research Database (Denmark)

    Bendixen, Carsten

    2014-01-01

    Bidrag med en kortfattet, introducerende, perspektiverende og begrebsafklarende fremstilling af begrebet test i det pædagogiske univers.......Bidrag med en kortfattet, introducerende, perspektiverende og begrebsafklarende fremstilling af begrebet test i det pædagogiske univers....

  1. Impact melt- and projectile-bearing ejecta at Barringer Crater, Arizona

    Science.gov (United States)

    Osinski, Gordon R.; Bunch, Ted E.; Flemming, Roberta L.; Buitenhuis, Eric; Wittke, James H.

    2015-12-01

    Our understanding of the impact cratering process continues to evolve and, even at well-known and well-studied structures, there is still much to be learned. Here, we present the results of a study on impact-generated melt phases within ejecta at Barringer Crater, Arizona, one of the first impact craters on Earth to be recognized and arguably the most famous. We report on previously unknown impact melt-bearing breccias that contain dispersed fragments of the projectile as well as impact glasses that contain a high proportion of projectile material - higher than any other glasses previously reported from this site. These glasses are distinctly different from so-called "melt beads" that are found as a lag deposit on the present-day erosion surface and that we also study. It is proposed that the melts in these impact breccias were derived from a more constrained sub-region of the melt zone that was very shallow and that also had a larger projectile contribution. In addition to low- and high-Fe melt beads documented previously, we document Ca-Mg-rich glasses and calcite globules within silicate glass that provide definitive evidence that carbonates underwent melting during the formation of Barringer Crater. We propose that the melting of dolomite produces Ca-Mg-rich melts from which calcite is the dominant liquidus phase. This explains the perhaps surprising finding that despite dolomite being the dominant rock type at many impact sites, including Barringer Crater, calcite is the dominant melt product. When taken together with our estimate for the amount of impact melt products dispersed on, and just below, the present-day erosional surface, it is clear that the amount of melt produced at Barringer Crater is higher than previously estimated and is more consistent with recent numerical modeling studies. This work adds to the growing recognition that sedimentary rocks melt during hypervelocity impact and do not just decompose and/or devolatilize as was previously thought

  2. Local Impact Simulation of SC Wall Structures using Aircraft Engine Projectile

    International Nuclear Information System (INIS)

    SC wall structure developed for nuclear power plant buildings consists of plain concrete and two steel plates on both surface of the concrete, while RC structure consists of re bar and concrete. SC structure has higher scabbing resistance than RC structure due to the action of steel plate on the rear side of impact. Therefore SC structure is known as more effective structure from the viewpoint of aircraft crash than RC structure. However, most of the recent researches and experiments about local impact damage deal with RC structures, and the effect of re bar and steel plate is not considered reasonably. Although Walter et al. and Make-work et al. suggested a formula for evaluating perforation depth of steel plate covered RC walls, most of the previous researches about SC structure are focused on perforation and scabbing due to the impact of hard projectile, rather than soft projectile such as an aircraft. In this research a soft projectile, i. e. aircraft engine, is utilized for impact simulation of RC and SC walls. To evaluate local damage of SC wall structures, parametric study with the variables of wall thickness and steel ratio of the cover plate is performed, and the results are compared with those of RC structures. Since scabbing was prevented by the steel plates, penetration mode of damage was observed in SC walls while scabbing damage was occurred in RC walls. It is confirmed that the rear steel plate not only contains concrete debris, but also reduces the internal damage of the concrete walls. Penetration depth of SC walls did not largely vary due to the increasing steel ratio, and similar results to RC walls were observed when the wall thickness is larger than a certain value since the impact resistance of SC wall is mainly governed by the thickness of concrete part. Therefore, it is expected that similar level of impact resistance to RC structure can be produced with the minimum thickness of steel plates of SC structure. According to these results, SC

  3. Comparative analysis of the 178m2Hf yield at reactions with different projectiles

    International Nuclear Information System (INIS)

    The long-lived high-spin 178m2Hf K-isomer can be produced in nuclear reactions with different projectiles. The reaction yields and cross-sections have been measured in a series of experiments and the results are now overviewed. The systematics of isomer-to-ground state ratios are drawn and real production capabilities are estimated for the best reactions. Such a summary is relevant to the significance of the isomer studies both for the nuclear-science knowledge and for possible applications. Potential isomer applications have been earlier stressed in popular publications with probably overestimated expectations. The real possibilities are restricted in part by the production yield and by other shortcomings as well

  4. Multiple-laser flash shadowgraphy system for terminal studies of small-caliber projectiles

    Science.gov (United States)

    Kalonia, R. C.; Mitra, Gautam; Singh, G. S.; Varma, R. K.; Singh, Manpreet; Singh, Manjit; Sethi, V. S.; Yadav, M. S.

    2010-06-01

    A multiple-laser flash shadowgraphy system has been innovatively designed and developed to study the terminal effects of projectiles. The system has been designed based on modulated laser diodes operated at low voltage and current. In order to study the ballistics effects of small arms, an exposure time of the order of a few hundreds ns and a delay time of the order of a few tens of μs are needed. An ultrashort pulse generator has been developed to provide the exposure and delay time pulses. The developed system has been integrated with a field lens assembly and camera assembly. To record the shadowgraphs, a target is placed near the center of the field lens and a bullet is fired from a fixed gun. The system is described, and experimental results and conclusions are reported.

  5. Intermediate mass fragment emission by 197Au projectiles at relativistic energy in nuclear emulsion

    International Nuclear Information System (INIS)

    The charge distribution of multifragment decays of 197Au projectiles at 10.6A GeV in nuclear emulsion is fitted with a power law. The correlations between the charges emitted are given as a function of the total charge confined in fragments Zbound for Z≥2, which is a measure of the violence of the collision. The observables of the present experiment are compared to the 197Au beam at 600A MeV in the domain of limiting fragmentation and they are also reproduced by the predictions of the statistical and the percolation models. Small changes in the values of some of these observables are revealed in the two energies

  6. Projectile X-ray emission in relativistic ion-atom collisions

    Energy Technology Data Exchange (ETDEWEB)

    Salem, Shadi Mohammad Ibrahim

    2010-03-16

    This work reports on the study of the projectile X-ray emission in relativistic ion-atom collisions. Excitation of K-shell in He-like uranium ions, electron capture into H-like uranium ions and Simultaneous ionization and excitation of initially He-like uranium ions have been studied using the experimental storage ring at GSI. For the K{sub {alpha}}{sub 1} and K{sub {alpha}}{sub 2} transitions originating from the excitation of the He-like uranium ions, no alignment was observed. In contrast, the Ly{sub {alpha}}{sub 1} radiation from the simultaneous ionization-excitation process of the He-like uranium ions shows a clear alignment. The experimental value leads to the inclusion of a magnetic term in the interaction potential. The capture process of target electrons into the highly-charged heavy ions was studied using H-like uranium ions at an incident energy of 220 MeV/u, impinging on N{sub 2} gas-target. It was shown that, the strongly aligned electrons captured in 2p{sub 3/2} level couple with the available 1s{sub 1/2} electron which shows no initial directional preference. The magnetic sub-state population of the 2p{sub 3/2} electron is redistributed according to the coupling rules to the magnetic sub-states of the relevant two-electron states. This leads to the large anisotropy in the corresponding individual ground state transitions contributing to the K{sub {alpha}}{sub 1} emission. From the K{sub {alpha}}{sub 1}/K{sub {alpha}}{sub 2} ratio, the current results show that the incoherent addition of the E1 and M2 transition components yield to an almost isotropic emission of the total K{sub {alpha}}{sub 1}. In contrast to the radiative electron capture, the experimental results for the K-shell single excitation of He-like uranium ions indicate that only the {sup 1}P{sub 1} level contributes to the K{sub {alpha}}{sub 1} transition. For this case, the anisotropy parameter {beta}{sub 20} was found to be -0.20{+-}0.03. This work also reports on the study of a two

  7. Total Fragmentation Cross Section of 158A GeV Lead Projectiles in Cu Target

    Institute of Scientific and Technical Information of China (English)

    Mukhtar Ahmed Rana; Shahid Manzoor

    2008-01-01

    Total fragmentation cross section for the reaction 158A Pb ions + Cu target is measured using the most sensitive track detector CR-39. Measured values are compared with calculations. Exposures of target-detector stack with 158A Pb projectiles are made at CERN-SPS beam facility. Results of calibration of CR-39 detector in a charge region (63 ≤Z≤83) are also reported, which can be used for high energy particle identification using CR-39 and in determination of partial charge changing cross sections. The charge resolution σz achieved by this technique is about 0.2e. A systematic dependence of total fragmentation cross section on target properties is revealed and the corresponding results are presented.

  8. Special features of isomeric ratios in nuclear reactions induced by various projectile particles

    Science.gov (United States)

    Danagulyan, A. S.; Hovhannisyan, G. H.; Bakhshiyan, T. M.; Martirosyan, G. V.

    2016-05-01

    Calculations for ( p, n) and (α, p3 n) reactions were performed with the aid of the TALYS-1.4 code. Reactions in which the mass numbers of target and product nuclei were identical were examined in the range of A = 44-124. Excitation functions were obtained for product nuclei in ground and isomeric states, and isomeric ratios were calculated. The calculated data reflect well the dependence of the isomeric ratios on the projectile type. A comparison of the calculated and experimental data reveals, that, for some nuclei in a high-spin state, the calculated data fall greatly short of their experimental counterparts. These discrepancies may be due to the presence of high-spin yrast states and rotational bands in these nuclei. Calculations involving various level-density models included in the TALYS-1.4 code with allowance for the enhancement of collective effects do not remove the discrepancies in the majority of cases.

  9. Determination of absolute transition probabilities in 128Xe via projectile Coulomb excitation

    International Nuclear Information System (INIS)

    Recently, lifetimes of low-lying excited states in 128Xe were measured using the plunger technique after projectile Coulomb excitation. This experiment was performed at the JYFL, Jyvaeskylae using the JUROGAM Ge-detector array and the Cologne coincidence plunger device equipped with an array of 32 small Si-detectors. The Si-detectors were used to measure the reaction kinematics by registering target-like nuclei scattered in forward direction. In order to cross-check the results obtained from the recoil distance Doppler shift analysis an evaluation of the measured excitation cross-sections was performed with the computer code GOSIA. In addition deorientation effects were investigated and effort was made to extract absolute quadrupole moments. Details of the experiment and the calculations are presented.

  10. Global optical-model potentials for the elastic scattering of sup(6,7)Li projectiles

    International Nuclear Information System (INIS)

    Simultaneous fits have been made to 44 6Li data sets covering the mass range 24-208 and the energy range 13-156 MeV in order to determine an average ('global') optical-model potential for 6Li scattering. A similar study has been made for 25 7Li data sets over the same mass range and an energy range of 28-88 MeV to find an average 7Li potential. With Saxon-Woods factors, constant values may be used for all parameters except for the depth of the imaginary potential which decreases in magnitude with increasing mass. The necessity of energy dependence, Coulomb correction and (for 7Li) a symmetry term is investigated. The variation of the integral properties of the potentials is discussed, and also a comparison is made for the two projectiles. Application of the global potentials is made to inelastic scattering and single-nucleon transfer reactions. (orig.)

  11. Experimental Investigation on the Ballistic Resistace of Metal Plates Subjected to Impact of Rigid Projectiles

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; DENG Yun-fei; CAO Zong-sheng

    2012-01-01

    The ballistic performance of monolithic and multi-layered steel plates impacted by ogival-nosed projectiles was investigated by using a gas gun experimentally.The total thickness of in-contact multi-layered target was equally to that of monolithic target.The results show that,for the high strength targets,the monolithic targets have greater ballistic limit velocities than multi-layered targets,and also the ballistic limit velocities of targets decrease with the increase of the number of layers.However,for the low strength targets,the monolithic targets have lower ballistic limit velocities than multi-layered targets.The differences in target capacity between various impact conditions can be related to the transitions of perforation mechanisms and failure models.

  12. Nuclear Fragmentation Induced by Relativistic Projectiles Studied in the 4$\\pi$ Configuration of Plastic Track Detectors

    CERN Multimedia

    2002-01-01

    % EMU19 \\\\ \\\\ The collisions of heavy ions at relativistic energies have been studied to explore a number of questions related with hot and dense nuclear matter in order to extend our knowledge of nuclear equation-of-state. There are other aspects of these interactions which are studied to expound the process of projectile and/or target disintegrations. The disintegrations in question could be simply binary fissions or more complex processes leading to spallation or complete fragmentation. These important aspects of nuclear reactions are prone to investigations with nuclear track detectors. \\\\ \\\\One of the comparatively new track detector materials, CR-39, is sensitive enough to record particles of Z~$\\geq$~6 with almost 100\\% efficiency up to highly relativistic energies. The wide angle acceptance and exclusive measurements possible with plastic track detectors offer an opportunity to use them in a variety of situations in which high energy charged fragments are produced. The off-line nature of measuring tra...

  13. Projectile fragmentation at intermediate energies and the production of light neutron rich exotic nuclei

    International Nuclear Information System (INIS)

    The possibility for projectile fragmentation with intermediate energy heavy ions (20< E<90MeV/u) to be a powerful 100l for producing new exotic species is illustrated here. The existing methods using heavy ions are first reviewed briefly. The mechanism responsible for fragment production at the Ganil energies is then described. The main features which are of interest as far as the production of n-rich nuclides is concerned will be emphasized. This will allow some predictions for the production rates of n-rich isotopes. The LISE spectrometer is then described and finally the results of the first experiment using the reaction Ar+Ta at 1,8 GeV where the neutron drip line has been reached for some light nuclei are presented

  14. Role of the granular nature of meteoritic projectiles in impact crater morphogenesis

    CERN Document Server

    Bartali, Roberto; Nahmad-Molinari, Yuri; Sarochi, Damiano; Ruiz-Suárez, J C

    2013-01-01

    By means of novel volume-diameter aspect ratio diagrams, we ponder on the current conception of crater morphogenesis analyzing crater data from beam explosions, hypervelocity collisions and drop experiments and comparing them with crater data from three moons (the Moon, Callisto, and Ganymede) and from our own experimental results. The distinctive volume-diameter scaling laws we discovered make us to conclude that simple and complex craters in satellites and planets could have been formed by granular vs. granular collisions and that central peaks and domes in complex craters were formed by a dynamic confinement of part of the impacting projectile, rather than by the uplift of the target terrain. A granulometric analysis of asteroids and central peaks and domes inside complex craters, shows boulder size distributions consistent with our hypothesis that crater internal features are the remnants of granular impactors.

  15. Investigation into debris cloud characterizations for oblique hypervelocity impact of projectiles on bumper

    Institute of Scientific and Technical Information of China (English)

    张伟; 管公顺; 庞宝君; 李强; 张永强

    2004-01-01

    All long-duration spacecraft in low-earth-orbit are subject to high velocity impacts by meteoroids and space debris. Such impacts are expected to occur at non-normal incidence angles and can cause severe damage to the spacecraft and its external flight-critical systems and possibly lead to catastrophic failure of the spacecraft.In order to ensure crew safety and proper function of internal and external spacecraft systems, the characteristics of a debris cloud generated by such impacts must be known. An analytical model is therefore developed for the characterization of the penetration and ricochet debris clouds created by the hypervelocity impact of an aluminum spherical projectile on an aluminum plate. This model employs normal and oblique shock wave theory to characterize the penetration and ricochet processes. The prediction results of center-of-mass trajectory and leading velocity of penetration and ricochet debris clouds are obtained and compared with numerical and experimental results in figures.

  16. Behaviour of Thin Aluminium Plates Subjected to Impact by Ogive-nosed Projectiles

    Directory of Open Access Journals (Sweden)

    M.A. Iqbal

    2006-11-01

    Full Text Available A pneumatic gas gun has been used to fire ogive-nosed projectiles on aluminium plates(1mm at varying impact velocities above the ballistic limit. Impact and residual velocities havebeen measured. Deformation of the target plate was studied. Experimental results formed thebasis of a subsequent finite element analysis of the problem using the ABAQUS 6.3 code. TheJohnson-Cook plastic flow and fracture model available in the code were utilised. Explicit finiteelement analysis has been performed to model the perforation phenomenon. Numerical resultswere significantly improved by reducing the element size up to a certain level beyond which nosignificant variation in the results was observed. Adaptive meshing has been found to be usefulin obtaining the accurate results and avoiding the problem of premature termination of theprogram due to excessive element distortion. Experimental and numerical results are comparedand a good agreement between the two has been found.

  17. Relativistic exotic nuclei as projectile beams. New perspectives of studies on the properties of nuclei

    International Nuclear Information System (INIS)

    Examinations of the production cross-sections and the kinematics permitted refinement of model concepts of the peripheral reactions in exotic nuclei at energies from 100 to 1000 A MeV. Due to the strong selectivity and resolution achieved it was possible to discover a large number of novel isotopes at the fragment separator FRS, despite the relatively low projectile beam intensities of the SIS. The two twice magic nuclei found, Ni 78 and Sn 100, are particularly interesting, as they could not be measured so far with other experimental systems. Fission of relativistic uranium ions proved to be a particularly successful process yielding many medium-heavy, neutron-rich nuclei. Insight into the structure of light neutron halos could be improved. The superlarge spatial dimensions of the nuclear halos is discussed. (orig./CB)

  18. Dynamic measurement of the influence of projectile radius and velocity on strain localization during impact of an energetic material

    Energy Technology Data Exchange (ETDEWEB)

    Asay, B.W.; Dickson, P.M.; Henson, B.; Fugard, C.; Funk, D.J.; Idar, D.J.

    1998-12-31

    A new technique for measuring the dynamic displacement fields during deformation has been developed. The method uses high speed laser-induced fluorescence speckle photography. The authors report the effect of projectile velocity and radius on the strain fields in a quasi-two dimensional confined sample of PBX 9501.

  19. Ionization of small molecules induced by H+, H e+ , and N+ projectiles: Comparison of experiment with quantum and classical calculations

    Science.gov (United States)

    Kovács, S. T. S.; Herczku, P.; Juhász, Z.; Sarkadi, L.; Gulyás, L.; Sulik, B.

    2016-07-01

    We report the energy and angular distribution of ejected electrons from C H4 and H2O molecules impacted by 1 MeV H+, H e+ , and 650 keV N+ ions. Spectra were measured at different observation angles, from 2 to 2000 eV. The obtained absolute double-differential electron-emission cross sections (DDCSs) were compared with the results of classical trajectory Monte Carlo (CTMC) and continuum distorted wave, eikonal initial state (CDW-EIS) calculations. For the bare H+ projectile both theories show remarkable agreement with the experiment at all observed angles and energies. The CTMC results are in similarly good agreement with the DDCS spectra obtained for impact by dressed H e+ and N+ ions, where screening effects and electron loss from the projectile gain importance. The CDW-EIS calculations slightly overestimate the electron loss for 1 MeV H e+ impact, and overestimate both the target and projectile ionization at low emitted electron energies for 650 keV N+ impact. The contribution of multiple electron scattering by the projectile and target centers (Fermi shuttle) dominates the N+-impact spectra at higher electron energies, and it is well reproduced by the nonperturbative CTMC calculations. The contributions of different processes in medium-velocity collisions of dressed ions with molecules are determined.

  20. Damage visualization and deformation measurement in glass laminates during projectile penetration

    Institute of Scientific and Technical Information of China (English)

    Elmar STRASSBURGER; Steffen BAUER; Gregor POPKO

    2014-01-01

    Transparent armor consists of glass-polymer laminates in most cases. The formation and propagation of damage in the different glass layers has a strong influence on the ballistic resistance of such laminates. In order to clarify the course of events during projectile penetration, an experimental technique was developed, which allows visualizing the onset and propagation of damage in each single layer of the laminate. A telecentric objective lens was used together with a microsecond video camera that allows recording 100 frames at a maximum rate of 1 MHz in a backlit photography set-up. With this technique, the damage evolution could be visualized in glass laminates consisting of four glass layers with lateral dimensions 500 mm ? 500 mm. Damage evolution was recorded during penetration of 7.62 mm AP projectiles with tungsten carbide core and a total mass of 11.1 g in the impact velocity range from 800 to 880 m/s. In order to measure the deformation of single glass plates within the laminates, a piece of reflecting tape was attached to the corresponding glass plate, and photonic Doppler velocimetry (PDV) was applied. With the photonic Doppler velocimeter, an infrared laser is used to illuminate an object to be measured and the Doppler-shifted light is superimposed to a reference light beam at the detector. The simultaneous visualization and PDV measurement of the glass deformation allow determining the deformation at the time of the onset of fracture. The analysis of the experimental data was supported by numerical simulations, using the AUTODYN commercial hydro-code.

  1. Damage visualization and deformation measurement in glass laminates during projectile penetration

    Directory of Open Access Journals (Sweden)

    Elmar Strassburger

    2014-06-01

    Full Text Available Transparent armor consists of glass-polymer laminates in most cases. The formation and propagation of damage in the different glass layers has a strong influence on the ballistic resistance of such laminates. In order to clarify the course of events during projectile penetration, an experimental technique was developed, which allows visualizing the onset and propagation of damage in each single layer of the laminate. A telecentric objective lens was used together with a microsecond video camera that allows recording 100 frames at a maximum rate of 1 MHz in a backlit photography set-up. With this technique, the damage evolution could be visualized in glass laminates consisting of four glass layers with lateral dimensions 500 mm × 500 mm. Damage evolution was recorded during penetration of 7.62 mm AP projectiles with tungsten carbide core and a total mass of 11.1 g in the impact velocity range from 800 to 880 m/s. In order to measure the deformation of single glass plates within the laminates, a piece of reflecting tape was attached to the corresponding glass plate, and photonic Doppler velocimetry (PDV was applied. With the photonic Doppler velocimeter, an infrared laser is used to illuminate an object to be measured and the Doppler-shifted light is superimposed to a reference light beam at the detector. The simultaneous visualization and PDV measurement of the glass deformation allow determining the deformation at the time of the onset of fracture. The analysis of the experimental data was supported by numerical simulations, using the AUTODYN commercial hydro-code.

  2. Radiolysis of astrophysical ice analogs by energetic ions: the effect of projectile mass and ice temperature.

    Science.gov (United States)

    Pilling, Sergio; Duarte, Eduardo Seperuelo; Domaracka, Alicja; Rothard, Hermann; Boduch, Philippe; da Silveira, Enio F

    2011-09-21

    An experimental study of the interaction of highly charged, energetic ions (52 MeV (58)Ni(13+) and 15.7 MeV (16)O(5+)) with mixed H(2)O : C(18)O(2) astrophysical ice analogs at two different temperatures is presented. This analysis aims to simulate the chemical and the physicochemical interactions induced by cosmic rays inside dense, cold astrophysical environments, such as molecular clouds or protostellar clouds as well at the surface of outer solar system bodies. The measurements were performed at the heavy ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds) in Caen, France. The gas samples were deposited onto a CsI substrate at 13 K and 80 K. In situ analysis was performed by a Fourier transform infrared (FTIR) spectrometer at different fluences. Radiolysis yields of the produced species were quantified. The dissociation cross section at 13 K of both H(2)O and CO(2) is about 3-4 times smaller when O ions are employed. The ice temperature seems to affect differently each species when the same projectile was employed. The formation cross section at 13 K of molecules such as C(18)O, CO (with oxygen from water), and H(2)O(2) increases when Ni ions are employed. The formation of organic compounds seems to be enhanced by the oxygen projectiles and at lower temperatures. In addition, because the organic production at 13 K is at least 4 times higher than the value at 80 K, we also expect that interstellar ices are more organic-rich than the surfaces of outer solar system bodies. PMID:21647477

  3. Role of projectile breakup effects and intrinsic degrees of freedom on fusion dynamics

    Science.gov (United States)

    Singh Gautam, Manjeet

    2016-05-01

    This article analyzes the fusion dynamics of loosely bound and stable projectiles with Zr-target isotopes within the context of the coupled channel approach and the energy-dependent Woods-Saxon potential model (EDWSP model). In the case of the 28Si + 90Zr reaction, the coupling to the inelastic surface excitations results in an adequate description of the observed fusion dynamics while in case of the 28Si + 94Zr reaction, the coupling to collective surface vibrational states as well as the neutron (multi-neutron) transfer channel is necessary in the coupled channel calculations to reproduce the below-barrier fusion data. However, the EDWSP model calculation provides an accurate explanation of the fusion data of 28Si + 90,94Zr reactions in the domain of the Coulomb barrier. In the fusion of the 6Li + 90Zr reaction, the inclusion of the nuclear structure degrees of freedom recovers the observed sub-barrier fusion enhancement but results in suppression of the above barrier fusion data by 34% with respect to the coupled channel calculations. Using EDWSP model calculations, this suppression factor is reduced by 14% and consequently, the above-barrier fusion data of 6Li + 90Zr reaction is suppressed by 20% with reference to the EDWSP model calculations. Such fusion suppression at above-barrier energies can be correlated with the breakup of the projectile (6Li) before reaching the fusion barrier, as a consequence of low binding energy. Supported by Dr. D. S. Kothari Post-Doctoral Fellowship Scheme sponsored by University Grants Commission (UGC), New Delhi, India

  4. Social Preferences: Some Simple Tests and a New Model.

    OpenAIRE

    Gary Charness and Matthew Rabin.

    2000-01-01

    JEL#: A12, A13, B49, C70, C91, D63 Keywords: difference aversion, fairness, inequality aversion, maximin criterion, non-ultimatum games, reciprocal fairness, social preferences Departures from pure self interest in economic experiments have recently inspired models of "social preferences". We conduct experiments on simple two-person and three-person games with binary choices that test these theories more directly than the array of games conventionally considered. Our experiments show strong s...

  5. Study of uranium dioxyde sputtering induced by multicharged heavy ions at low and very low kinetic energy: projectile charge effect

    International Nuclear Information System (INIS)

    Ion beam irradiation of a solid can lead to the emission of neutral or ionized atoms, molecules or clusters from the surface. This comes as a result of the atomic motion in the vicinity of the surface, induced by the transfer of the projectile energy. Then, the study of the sputtering process appears as a means to get a better understanding of the excited matter state around the projectile trajectory. In the case of slow multicharged ions, a strong electronic excitation can be achieved by the projectile neutralization above the solid surface and / or its deexcitation below the surface. Parallel to this, the slowing down of such ions is essentially related to elastic collision with the target atoms. The study of the effect of the initial charge state of slow multicharged ions, in the sputtering process, has been carried out by measuring the absolute angular distributions of emission of uranium atoms from a uranium dioxide surface. The experiments have been performed in two steps. First, the emitted particles are collected onto a substrate during irradiation. Secondly, the surface of the collectors is analyzed by Rutherford Backscattering Spectrometry (RBS). This method allows the characterization of the emission of neutrals, which are the vast majority of the sputtered particles. The results obtained provide an access to the evolution of the sputtering process as a function of xenon projectile ions charge state. The measurements have been performed over a wide kinetic energy range, from 81 down to 1.5 keV. This allowed a clear separation of the contribution of the kinetic energy and initial projectile charge state to the sputtering phenomenon. (author)

  6. Korekcija putanje žiroskopski stabilisanog projektila primenom proporcionalne navigacije / Trajectory correction of gyroscopic stabilized projectile using proportional navigation

    Directory of Open Access Journals (Sweden)

    Danilo V. Ćuk

    2010-01-01

    Full Text Available U radu su prikazane metode korekcije putanje žiroskopski stabilisanih projektila primenom proporcionalne navigacije. Sekcija upravljanja tipa 'patka' ugrađena je na klasični projektil radi generisanja aerodinamičke sile. Efikasnost projektila sa korekcijom putanje prikazana je pomoću rezultata numeričke simulacije leta, primenom proporcionalne navigacije sa i bez kompenzacije poremećaja zbog gravitacionog i tangentnog ubrzanja. Analizirani su, takođe, uticaji početnog ugla elevacije i odstupanja ravni upravljanja od ravni praćenja cilja na promašaj projektila. Pokazano je da se precesioni oblik oscilovanja ugaonog kretanja projektila prenosi na ugaonu brzinu linije viziranja cilja koju treba filtrirati kako bi se otklonila pojava rezonantne nestabilnosti leta projektila. / This paper presents the methods of the trajectory correction of gyroscopic stabilized projectiles using different modifications of proportional navigation. The canard section is built into the conventional projectile to generate aerodynamic force. The effectiveness of the trajectory correctable projectile is shown by the results of a flight numerical simulation using proportional navigation with and without the compensation of the disturbance due to gravitational and tangent acceleration. The paper also analyzes the effects of the initial elevation angle and the deflection of the control plane from the target tracking one on the miss distance. It is shown that the precessional mode of the projectile angular motion is transferred to the line of sight rate which should be filtered to prevent the phenomenon of resonance instability of the projectile flight.

  7. Ejecta velocity distribution of impact craters formed on quartz sand: Effect of projectile density on crater scaling law

    Science.gov (United States)

    Tsujido, Sayaka; Arakawa, Masahiko; Suzuki, Ayako I.; Yasui, Minami

    2015-12-01

    In order to clarify the effects of projectile density on ejecta velocity distributions for a granular target, impact cratering experiments on a quartz sand target were conducted by using eight types of projectiles with different densities ranging from 11 g cm-3 to 1.1 g cm-3, which were launched at about 200 m s-1 from a vertical gas gun at Kobe University. The scaling law of crater size, the ejection angle of ejecta grains, and the angle of the ejecta curtain were also investigated. The ejecta velocity distribution obtained from each projectile was well described by the π-scaling theory of v0/√{gR} =k2(x0/R)-1/μ, where v0, g, R and x0 are the ejection velocity, gravitational acceleration, crater radius and ejection position, respectively, and k2 and μ are constants mostly depending on target material properties (Housen, K.R., Holsapple, K.A. [2011]. Icarus 211, 856-875). The value of k2 was found to be almost constant at 0.7 for all projectiles except for the nylon projectile, while μ increased with the projectile density, from 0.43 for the low-density projectile to 0.6-0.7 for the high-density projectile. On the other hand, the π-scaling theory for crater size gave a μ value of 0.57, which was close to the average of the μ values obtained from ejecta velocity distributions. The ejection angle, θ, of each grain decreased slightly with distance, from higher than 45° near the impact point to 30-40° at 0.6 R. The ejecta curtain angle is controlled by the two elementary processes of ejecta velocity distribution and ejection angle; it gradually increased from 52° to 63° with the increase of the projectile density. The comparison of our experimental results with the theoretical model of the crater excavation flow known as the Z-model revealed that the relationship between μ and θ obtained by our experiments could not be described by the Z-model (Maxwell, D.E. [1977]. In: Roddy, D.J., Pepin, R.O., Merrill, R.B. (Eds.), Impact and Explosion Cratering

  8. 考虑刚性弹弹头形状的混凝土(岩石)靶体侵彻深度半理论分析%Semi-theoretical analyses for penetration depth of rigid projectiles with different nose geometries into concrete (rock) targets

    Institute of Scientific and Technical Information of China (English)

    吴昊; 方秦; 龚自明

    2012-01-01

    Based on the dynamic spherical cavity-expansion theory and the two-stage penetration model consisting of cratering and tunneling, a dimensionless formula was proposed for normal penetration depth of rigid projectiles into concrete and rock targets by taking a truncated-ogive nose projectile as an example. In the proposed formula, the surface integration method was applied, and the mass ratio and the impact factor were introduced, as well as the dimensionless coefficients denoting the projectile nose geometry and the projectile-target friction effect, to consider the variation of projectile nose geometry, cratering depth, and tangential resistance on projectiles. And the proposed formula can be regressed to the classic penetration formulae in special cases. The proposed formula was validated by comparing the penetration depths predicted by the proposed formula with those predicted by the existing ten classic empirical and semi-empirical formulae as well as the experimental data from eight field shot tests of concrete and rock targets hit by projectiles with different nose geometries. Based on the tests and parametric analyses, the corresponding parameter values were recommended aiming to different nose projectiles, including the dynamic projectile-target frictional coefficient of concrete and rock targets, as well as the linear coefficient of cratering depth related to the impact factor.%基于动力球型空腔膨胀理论和“冲击成坑+钻孔区”两阶段侵彻模型,以截卵形弹头弹体为例,运用曲面积分,引入表征弹头形状和弹靶摩擦效应的量纲—系数、质量比和冲击因子,提出了综合考虑弹头形状变化、成坑区深度、弹靶摩擦阻力的混凝土和岩石靶体的刚性弹垂直侵彻深度的计算公式.该公式在相关参数取特殊值时,可退化为经典的侵彻深度计算公式.通过与8组不同弹头形状弹体冲击混凝土和岩石靶体的侵彻实验数据、已有10个(半)经验公式

  9. Numerical Study on Anti-Penetration Process of Alumina Ceramic (AD95) to Tungsten Long Rod Projectiles

    Science.gov (United States)

    Zhang, Xianfeng; Zhang, Niansong; Li, Yongchi

    Numerical studies were conducted on the ballistic performance of alumina ceramic (AD95) tiles based on depth of penetration method, when subjected to normal impact of tungsten long rod projectiles at velocities ranging from 1100 to 2000 ms-1. The residual depth on after-effect target was derived in each case, and the ballistic efficiency factor was determined using the corresponding penetration depth on medium carbon steel. Anti-penetration experiment study of the AD95 ceramic tiles to tungsten long rod projectiles has been carried out to verify the accuracy of numerical simulation model. The result shows that numerical simulation results agree well with the corresponding experiment results and AD95 ceramic has excellent ballistic performance than medium carbon steel. The ballistic efficiency factor increases with velocity increasing when impact velocity lower than 1300 ms-1, and when it was higher than 1300 ms-1 the ballistic efficiency factor has almost no difference.

  10. Satellite splat II: an inelastic collision with a surface-launched projectile and the maximum orbital radius for planetary impact

    Science.gov (United States)

    Blanco, Philip R.; Mungan, Carl E.

    2016-07-01

    Starting with conservation of energy and angular momentum, we derive a convenient method for determining the periapsis distance of an orbiting object, by expressing its velocity components in terms of the local circular speed. This relation is used to extend the results of our previous paper, examining the effects of an adhesive inelastic collision between a projectile launched from the surface of a planet (of radius R) and an equal-mass satellite in a circular orbit of radius r s. We show that there is a maximum orbital radius r s ≈ 18.9R beyond which such a collision cannot cause the satellite to impact the planet. The difficulty of bringing down a satellite in a high orbit with a surface-launched projectile provides a useful topic for a discussion of orbital angular momentum and energy. The material is suitable for an undergraduate intermediate mechanics course.

  11. Identification des coefficients aérodynamiques d'un projectile à partir de mesures prises en vol

    OpenAIRE

    Demailly, Hélène

    2011-01-01

    La maîtrise du comportement en vol d'un projectile est, en partie, conditionnée par la connaissance des coefficients associés à chaque effort aérodynamique. Différents outils sont utilisés dans l'industrie, tels que les codes numériques aérodynamiques ou les essais en soufflerie, afin d'obtenir une première estimation des coefficients en phase d'avant-projet. Il est ensuite nécessaire de vérifier la valeur des coefficients et de valider le comportement du projectile en vol au moyen de tirs in...

  12. Impact cratering experiments into quartzite, sandstone and tuff: The effects of projectile size and target properties on spallation

    Science.gov (United States)

    Poelchau, Michael H.; Kenkmann, Thomas; Hoerth, Tobias; Schäfer, Frank; Rudolf, Michael; Thoma, Klaus

    2014-11-01

    Impact cratering experiments were performed on quartzite, tuff, and dry and water-saturated sandstones in the framework of the MEMIN research unit. 2.5-12 mm diameter projectiles were accelerated to ∼5 km/s. Evaluation of the resulting craters shows that crater volumes and crater efficiencies of large-scale experiments are greater than predicted by strength scaling laws. A method to approximate the transient crater volume shows that this effect is largely due to an increase in spallation. Strength scaling laws are used to determine the reduction of tensile strength in large-scale experiments and show a decrease by a factor of 1.8-3.6. This strength reduction can be correlated with a decrease in strain rate for larger projectiles, and with the Weibull theory of strength reduction for larger rock sample sizes. Further variations in spallation are observed between different target materials; a decrease in spall is suggested to be controlled by increased porosity.

  13. Charge correlations in the breakup of gold projectiles in reactions at E/A=600 MeV

    International Nuclear Information System (INIS)

    In the present thesis the charge correlations in the breakup of gold projectiles in heavy ion collisions at an incident energy of E/A=600 MeV were studied. Thereby it has been proved that the sum of the charges from the projectile source under exclusion of the protons (Zbound) is saliently suited for the classification of the nuclear reactions. At large values of Zbound we fins fission and spallation reactions. For smaller values of Zbound we observe events with an increasing number of medium-heavy fragments. Thereby the multifragment events appear in the Dalitz diagrams as a continuation of more symmetric becoming spallation events. In reactions with Zbound ≅ 35 the conditions for the formation of medium-heavy fragments are optimal and the multifragment events represent the dominating exit channel. A mean multiplicity of the medium-heavy fragments of ≅ 4 is reached. (orig./HSI)

  14. Effects of projectile resonances on the total, Coulomb, and nuclear breakup cross sections in the 6Li+152Sm reaction

    Science.gov (United States)

    Mukeru, B.; Lekala, M. L.

    2016-08-01

    In this paper we analyze the effects of the projectile resonances on the total, Coulomb, and nuclear breakup cross sections as well as on the Coulomb-nuclear interferences at different arbitrary incident energies. It is found that these resonances have non-negligible effects on the total, Coulomb, and nuclear breakup cross sections. Qualitatively, they have no effects on the constructiveness or destructiveness of the Coulomb-nuclear interferences. Quantitatively, we obtained that these resonances increase by 7.38%, 7.58%, and 20.30% the integrated total, Coulomb, and nuclear breakup cross sections, respectively at Elab=35 MeV . This shows that the nuclear breakup cross sections are more affected by the effects of the projectile resonances than their total and Coulomb breakup counterparts. We also obtain that the effects of the resonances on the total, Coulomb, and nuclear breakup cross sections decrease as the incident energy increases.

  15. Fraunhofer-type diffraction patterns of matter-wave scattering of projectiles: Electron transfer in energetic ion-atom collisions

    Science.gov (United States)

    Agueny, Hicham

    2015-07-01

    We present results for single and double electron captures in intermediate energies H+ and 2H+ projectiles colliding with a helium target. The processes under investigations are treated using a nonperturbative semiclassical approach in combination with Eikonal approximation to calculate the scattering differential cross sections. The latter reveals pronounced minima and maxima in the scattering angles, in excellent agreement with the recent experimental data. It turns out that the present structure depends strongly on the projectile energy and shows only slight variations with different capture channels. The observed structure demonstrates the analogy of atomic de Broglie's matter-wave scattering with λd B=1.3 -3.2 ×10-3 a.u. and Fraunhofer-type diffraction of light waves.

  16. Comparison of mid-velocity fragment formation with projectile-like decay

    CERN Document Server

    Hudan, S; Davin, B; Larochelle, Y; Xu, H; Beaulieu, L; Lefort, T; Yañez, R; De Souza, R T; Charity, R J; Sobotka, L G; Liu, T X; Liu, X D; Lynch, W G; Shomin, R; Tan, W P; Tsang, M B; Molen, A V; Wagner, A; Xi, H F

    2005-01-01

    The characteristics of intermediate mass fragments (IMFs: 3<=Z<=20) produced in mid-peripheral and central collisions are compared. We compare IMFs detected at mid-velocity with those evaporated from the excited projectile-like fragment (PLF*). On average, the IMFs produced at mid-velocity are larger in atomic number, exhibit broader transverse velocity distributions, and are more neutron-rich as compared to IMFs evaporated from the PLF*. In contrast, comparison of mid-velocity fragments associated with mid-peripheral and central collisions reveals that their characteristics are remarkably similar despite the difference in impact parameter. The characteristics of mid-velocity fragments are consistent with low-density formation of the fragments. Neutron deficient isotopes of even Z elements manifest higher kinetic energies than heavier isotopes of the same element for both PLF* and mid-velocity emission. This result may be due to the decay of long-lived excited states in the field of the emitting system.

  17. Interplay of projectile breakup and target excitation in reactions induced by weakly-bound nuclei

    CERN Document Server

    Gomez-Ramos, M

    2016-01-01

    In this work, we reexamine the extension of the CDCC formalism to include target excitation and apply it to a variety of reactions to study the effect of breakup on inelastic cross sections. We use a transformed oscillator basis to discretize the continuum of the projectiles in the different reactions and use the extended CDCC method developed in this work to solve the resulting coupled differential equations. A new code has been developed to perform the calculations. Reactions 58Ni(d, d) 58Ni*, 24Mg(d, d) 24Mg* , 144Sm( 6Li, 6Li) 144Sm* and 9Be( 6Li, 6Li) 9Be* are studied. Satisfactory agreement is found between experimental data and extended CDCC calculations. The studied CDCC method is proved to be an accurate tool to describe target excitation in reactions with weakly-bound nuclei. Moderate effects of breakup on inelastic observables are found for the reactions studied. Cross section magnitudes are not modified much, but angular distributions present smoothing when opposed to calculations without breakup.

  18. Proof-of-concept development of PXAMS (projectile x-ray accelerator mass spectrometry)

    Energy Technology Data Exchange (ETDEWEB)

    Proctor, I.D.; Roberts, M.L.; McAninch, J.E.; Bench, G.S.

    1996-03-01

    Prior to the current work, accelerator mass spectrometry (AMS) was limited to a set of {approximately}8--10 isotopes. This limitation is caused primarily by the inability to discriminate against stable atomic isobars. An analysis scheme that combines the isotopic sensitivity of AMS with similar isobar selectivity would open a large new class of isotope applications. This project was undertaken to explore the use of characteristic x rays as a method for the detection and identification of ions,and to allow the post-spectrometer rejection of isobaric interferences for isotopes previously inaccessible to AMS. During the second half of FY94 (with Advanced Concepts funding from the Office of Non-Proliferation and National Security), we examined the feasability of this technique, which we are referring to as PXAMS (Projectile X ray AMS), to the detection of several isotopes at Lawrence Livermore National Laboratory (LLNL). In our first exploratory work, we measured the x ray yield vs energy for {sup 80}Se ions stopped in a thick Y target. These results, demonstrated that useful detection efficiencies could be obtained for Se ions at energies accessible with our accelerator, and that the count rate from target x rays is small compared to the Se K{alpha} rate. We followed these measurements with a survey of x ray yields for Z = 14-46.

  19. Sensitivity of N/Z ratio in projectile break-up of isobaric systems

    Directory of Open Access Journals (Sweden)

    De Filippo E.

    2016-01-01

    Full Text Available The binary break-up of projectile-like fragments in non central heavy-ion collisions follows different decay patterns, from equilibrated emission towards dynamical (prompt fission. Recently, comparing two systems with different N/Z in the entrance channel, it has been shown that the dynamical emission cross-section is enhanced for the most neutron rich system while the statistical emission cross-section is independent from the isotopic composition. In order to understand this dependence and disentangle it from the initial size of the nuclei, we have studied the two isobaric systems 124Xe+64 Zn and 124Xe+64 Ni at 35 A MeV (InKiIsSy experiment, in comparison with the previous studied reactions (124Sn +64 Ni and 112Sn +58 Ni at the same bombarding energy. We present the first results evidencing a striking similar effect in the dynamical decay as a function of the N/Z of the target for equal size systems.

  20. Failure mechanism of monolayer graphene under hypervelocity impact of spherical projectile.

    Science.gov (United States)

    Xia, Kang; Zhan, Haifei; Hu, De'an; Gu, Yuantong

    2016-01-01

    The excellent mechanical properties of graphene have enabled it as appealing candidate in the field of impact protection or protective shield. By considering a monolayer graphene membrane, in this work, we assessed its deformation mechanisms under hypervelocity impact (from 2 to 6 km/s), based on a serial of in silico studies. It is found that the cracks are formed preferentially in the zigzag directions which are consistent with that observed from tensile deformation. Specifically, the boundary condition is found to exert an obvious influence on the stress distribution and transmission during the impact process, which eventually influences the penetration energy and crack growth. For similar sample size, the circular shape graphene possesses the best impact resistance, followed by hexagonal graphene membrane. Moreover, it is found the failure shape of graphene membrane has a strong relationship with the initial kinetic energy of the projectile. The higher kinetic energy, the more number the cracks. This study provides a fundamental understanding of the deformation mechanisms of monolayer graphene under impact, which is crucial in order to facilitate their emerging future applications for impact protection, such as protective shield from orbital debris for spacecraft. PMID:27618989

  1. Study of Relativistic Nucleus-nucleus Coll.Induced by 16O Projectiles

    CERN Multimedia

    2002-01-01

    A double experiment in which two detector systems (Streamer Chamber, Plastic Ball Calorimeter), running concurrently via a beam split (West Area H3, X5), search for quark matter formation in violent collisions of |1|6O or |2|0Ne with target nuclei between |4|0Ca and |2|0|6Pb. The acceleration of |1|6O will be facilitated by a high charge state injector, consisting of an ECR source and an RFQ pre-accelerator, installed by GSI and LBL at the PS Linac 1. Experimental equipment will be a streamer chamber installed in the Vertex Magnet of experiment WA75 together with beam hodoscopes and a downstream trigger calorimeter selecting violent events by the absence of energy flow to the projectile fragmentation region. Observed particles will be p, @p, K|0, @L and @L. In addition there will be the Plastic Ball, 800-fold @DE-E particle identifier system, covering the target fragmentation and backward fireball regions. Together with a multisegmented large solid angle (@+~9|0 of beam) energy calorimeter and a trigger calor...

  2. Energy loss of /sup 12/C projectiles in different carbon modifications

    International Nuclear Information System (INIS)

    The stopping cross sections of the three carbon modifications diamond, graphite, and glassy carbon are investigated for carbon projectiles of intermediate velocity. The inverted Doppler-shift attenuation method was used as the experimental technique, and it enabled us to measure the ratios of the three stopping cross sections precisely over a wide energy range. For velocities between 3 and 4 times Bohr's velocity the stopping cross sections of graphite and glassy carbon are found to be 1.036 and 1.072 times larger than that of diamond, respectively. These differences are attributed to binding effects. To understand these effects, we have evaluated the mean ionization potentials utilizing the local-plasma approximation for the inner-shell electrons and the dielectric response function for the valence electrons. The theoretical ratios calculated by inserting these potentials into the Bethe-Bloch stopping-power formula agree well with our experimental results. Furthermore, we have obtained a value of 53.3 +- 4.1 fs for the lifetime of the first excited state of the /sup 12/C nucleus

  3. Protection of Cities from Small Rockets, Missiles, Projectiles and Mortar Shells

    CERN Document Server

    Bolonkin, Alexander

    2008-01-01

    The authors suggest a low cost closed AB-Dome, which may protect small cities such as Sederot from rockets, mortar shells, chemical and biological weapons. The offered AB-Dome is also very useful in peacetime because it protects the city from outside weather (violent storms, hail) and creates a fine climate within the Dome. The roughly hemispherical AB-Dome is a gigantic inflated thin transparent film, located at altitude up to 1 - 5 kilometers, which converts the city into a closed-loop air system. The film may be armored with a basalt or steel grille or cloth pocket-retained stones that destroy (by collision or detonation) incoming rockets, shells and other projectiles. Such an AB-Dome would even protect the city in case of a third-party nuclear war involving temporary poisoning of the Earth atmosphere by radioactive dust. The building of the offered dome is easy; the film spreads on the ground, the fan engines turn on and the cover rises to the needed altitude and is supported there by a small internal ove...

  4. Large-scale 3D modeling of projectile impact damage in brittle plates

    Science.gov (United States)

    Seagraves, A.; Radovitzky, R.

    2015-10-01

    The damage and failure of brittle plates subjected to projectile impact is investigated through large-scale three-dimensional simulation using the DG/CZM approach introduced by Radovitzky et al. [Comput. Methods Appl. Mech. Eng. 2011; 200(1-4), 326-344]. Two standard experimental setups are considered: first, we simulate edge-on impact experiments on Al2O3 tiles by Strassburger and Senf [Technical Report ARL-CR-214, Army Research Laboratory, 1995]. Qualitative and quantitative validation of the simulation results is pursued by direct comparison of simulations with experiments at different loading rates and good agreement is obtained. In the second example considered, we investigate the fracture patterns in normal impact of spheres on thin, unconfined ceramic plates over a wide range of loading rates. For both the edge-on and normal impact configurations, the full field description provided by the simulations is used to interpret the mechanisms underlying the crack propagation patterns and their strong dependence on loading rate.

  5. Role of projectile breakup in {sup 6}He and {sup 6}Li induced fusion reactions around barrier energies

    Energy Technology Data Exchange (ETDEWEB)

    Kumari, Anju; Kharab, Rajesh, E-mail: kharabrajesh@rediffmail.com

    2015-09-15

    The influence of projectile breakup on fusion cross section for {sup 6}He + {sup 209}Bi, {sup 6}He + {sup 64}Zn, {sup 6}Li + {sup 209}Bi and {sup 6}Li + {sup 64}Zn reactions at near barrier energies is studied within the framework of quantum diffusion approach. The breakup does not affect the fusion induced by {sup 6}He, whereas a significant suppression for {sup 6}Li induced reaction is observed in below barrier energy region.

  6. Enhanced excitation of Giant Pairing Vibrations in heavy-ion reactions induced by weakly-bound projectiles

    CERN Document Server

    Fortunato, L; Sofia, H M; Vitturi, A

    2002-01-01

    The use of radioactive ion beams is shown to offer the possibility to study collective pairing states at high excitation energy, which are not usually accessible with stable projectiles because of large energy mismatch. In the case of two-neutron stripping reactions induced by 6He, we predict a population of the Giant Pairing Vibration in 208Pb or 116Sn with cross sections of the order of a millibarn, dominating over the mismatched transition to the ground state.

  7. Energy, target, projectile and multiplicity dependences of intermittency behaviour in high energy O(Si,S) induced interactions

    International Nuclear Information System (INIS)

    Fluctuations of charged particles in high energy oxygen, silicon and sulphur induced interactions are investigated with the method of scaled factorial moments. It is found that for decreasing bin size down to δη∝0.1 the EMU01 data exhibits intermittent behaviour. The intermittency indexes are found to decrease with increasing incident energy and multiplicity and to increase with increasing target mass. It seems also to increase as the projectile mass increases. (orig.)

  8. Helium projectile fragment emission in interactions of 197Au with emulsion at 10.7A GeV

    International Nuclear Information System (INIS)

    The total and partial production cross-sections of the multiple helium fragments emitted in 10.7A GeV 197Au–emulsion interactions are reported and compared with those obtained from different projectiles at high energies. The multiplicity distributions of the helium fragments exhibit a KNO scaling. The dependence of Cq moments and on the mass number of the incident beams is plotted. (author)

  9. Interior Ballistics Two-Phase Reactive Flow Model Applied to Large Caliber Guided Projectile-Gun System

    OpenAIRE

    Mahmoud Rashad; XiaoBing Zhang; Hazem El Sadek

    2014-01-01

    Transient complex phenomena take place in a gun during interior ballistic cycle. Understanding these phenomena clearly and describing the mathematical models accurately are crucial to predict the behavior of gun system considering firing safety and performance. A mathematical model based on Eulerian-Eulerian approach for reactive gas-solid flow arising during interior ballistic cycle inside large caliber naval gun guided projectile system was developed. The model included the governing equati...

  10. Mechanisms of Energy Transfer from Hadronic and Nuclear Projectiles into Target Nuclei in Collisions at High Energies

    International Nuclear Information System (INIS)

    Mechanisms of energy transfer from high energy hadronic and nuclear projectiles to nuclear targets were investigated experimentally. The transfer is realized in two cardinal processes: in passage of the hadron through layers of intranuclear matter accompanied by emission of nucleons with energies from about 20 to about 400 MeV; in the particle production process, this process goes through intermediate objects. 19 refs., 1 tab

  11. Devices for launching 0. 1-g projectiles to 150 km/s or more to initiate fusion. Part 2. Railgun accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Hawke, R.S.

    1979-07-06

    The possibility of using a railgun accelerator to launch 0.1-g projectiles to hypervelocities (150 km/s or more) to initiate thermonuclear fusion is studied. The analysis revealed that a railgun with a plasma-arc armature is a viable approach to the goal. When calculating the railgun's probable performance, it was discovered that this launch system might possibly be designed to avoid adverse effects from boundary layer drag. An appendix provided by A.C. Buckingham summarizes his calculations that predict the amount of erosive drag between projectile and rail. Finally, it was found that certain properties of railgun and projectile materials can impose operational limits. Using these limits, single- and multistage accelerators were designed. Within such limits, a railgun could accelerate a 0.1-g projectile to hypervelocities.

  12. Devices for launching 0.1-g projectiles to 150 km/s or more to initiate fusion. Part 2. Railgun accelerators

    International Nuclear Information System (INIS)

    The possibility of using a railgun accelerator to launch 0.1-g projectiles to hypervelocities (150 km/s or more) to initiate thermonuclear fusion is studied. The analysis revealed that a railgun with a plasma-arc armature is a viable approach to the goal. When calculating the railgun's probable performance, it was discovered that this launch system might possibly be designed to avoid adverse effects from boundary layer drag. An appendix provided by A.C. Buckingham summarizes his calculations that predict the amount of erosive drag between projectile and rail. Finally, it was found that certain properties of railgun and projectile materials can impose operational limits. Using these limits, single- and multistage accelerators were designed. Within such limits, a railgun could accelerate a 0.1-g projectile to hypervelocities

  13. Comparison of high speed movie and flash x-ray measurement of the translational and rotational motions of projectiles penetrating gelatin

    International Nuclear Information System (INIS)

    Projectiles penetrating a gelatin block were simultaneously measured by a high speed movie camera, Dynafax, and by a sequential, orthogonal, flash x-ray system. The eight orthogonal views of the x-ray system provided position and orientation of the projectiles vs. time. From onset of tumble in the gelatin, owing to gyroscopic instability, the growth of yaw was the same for each round in a replicated set. This phenomenon provided a legitimate procedure for pooling the x-ray data, giving well determined curves of velocity decay and yaw growth. The movie camera observed the progress of the cavity formed by the projectile. The resulting velocity decay of the cavity tip was compared to that of the projectile as measured by the x-ray technique. (author)

  14. Production of helium projectile fragment in 84Kr-emulsion collisions at 1.7 A GeV

    International Nuclear Information System (INIS)

    Multiplicity, projected angular and transverse momentum distributions of helium projectile fragment (HPF) produced from 1.7 A GeV 84Kr induced different type of emulsion targets (H, CNO and AgBr) interactions are studied. It is found that the distributions of HPF from 84Kr–H, CNO, AgBr and emulsion interactions can be well explained by two Gaussian distributions. These imply the existence of two distinct emission sources (cold and hot source) of HPF in 84Kr–H, CNO, AgBr and emulsion interactions. The dominant source is the cold one (projectile spectator source) with lower temperature and the other is hot one (projectile participant source) with higher temperature. The temperature parameters of cold and hot source are obtained from pt2 distribution fitting using two Rayleigh distribution, which is independent of the target size within experimental errors. - Highlights: ► Multiplicity distribution can be well represented by two Gaussian distributions. ► Projected angular distributions can be well fitted by two Gaussian distributions. ► Transverse momentum distribution can be well explained by two Gaussian distributions. ► The temperature of emission sources is obtained from pt2 distribution. ► The temperature parameter is independent of the target size

  15. Penetration Evaluation of Explosively Formed Projectiles Through Air and Water Using Insensitive Munition: Simulative and Experimental Studies

    Directory of Open Access Journals (Sweden)

    M. Ahmed

    2016-02-01

    Full Text Available The process of formation, flying, penetration of explosively-formed projectiles (EFP and the effect of water on performance of the charge for underwater applications is simulated by Ansysis Autodyn 2D-Hydro code. The main objective of an explosively formed projectile designed for underwater applications is to disintegrate the target at longer standoff distances. In this paper we have simulated the explosively formed projectile from OFHC-Copper liner for 1200 conical angle. The Affect of water on the penetration of EFP is determined by simulations from Ansysis Autodyn 2-D Hydrocode and by varying depth of water from 1CD-5CD. The depth of penetration against steel target is measured experimentally. Flash X-Ray Radiography (FXR is used to capture EFP jet formation and its penetration against target is measured by depth of penetration experiments. Simulation results are compared with experimental results. The difference in simulated and experimental results for depth of penetration is about 7 mm, which lies within favorable range of error. The jet formation captured from FXR is quite clear and jet velocity determined from Flash X-ray radiography is the same as the ones obtained by using other high explosives. Therefore, it is indicated that Insensitive Munition (8701 can be utilized instead of Polymer Bonded Explosives (PBX for air and underwater environments with great reliability and without any hazard.

  16. Observation of anomalous reaction mean free paths of nuclear-projectile fragments in research emulsion from 2 A GeV heavy-ion collisions

    International Nuclear Information System (INIS)

    From an analysis of 1460 projectile fragment collisions in nuclear research emulsion exposed to 2.1 A GeV 16O and 1.9 A GeV 56Fe at the Bevalac, evidence is presented for the existence of an anomalously short interaction mean free path of projectile fragments for the first several cm after emission. The result is significant to beyond the 3 standard deviation confidence level

  17. Recent precision experiments with exotic nuclei produced with uranium projectiles and experimental prospects at FAIR

    International Nuclear Information System (INIS)

    Precision experiments with relativistic fragments separated in-flight require special experimental methods to overcome the inherent large emittance from the creation in nuclear reactions and atomic interactions in matter. At GSI relativistic exotic nuclei have been produced via uranium projectile fragmentation and fission and investigated with the in- flight separator FRS directly, or in combination with either the storage-cooler ring ESR or the FRS Ion Catcher. 1000 A*MeV 238U ions were used to create 60 new neutron-rich isotopes separated and identified with the FRS to measure their production cross sections. In another experimental campaign the fragments were separated in flight and injected into the storage-cooler ring ESR for accurate mass and lifetime measurements. In these experiments we have obtained accurate new mass values analyzed via a novel method which has reduced the systematic errors for both Schottky Mass Spectrometry (SMS) and for Isochronous Mass Spectrometry (IMS). Pioneering experiments have been carried out with the FRS Ion Catcher consisting of 3 experimental components, the dispersive magnetic system of the FRS with a monoenergetic and a homogeneous degrader, a cryogenic stopping cell filled with pure helium and a multiple-reflection time-of flight mass separator. The FRS Ion Catcher enables high precision spectroscopy experiments with eV to keV exotic nuclides. Results from these different FRS experiments are presented in this overview together with prospects for the next-generation facility Super-FRS. The novel features of the Super-FRS compared with the present FRS will be discussed in addition. (authors)

  18. Recent Precision Experiments with Exotic Nuclei Produced with Uranium Projectiles and Experimental Prospects at Fair

    Directory of Open Access Journals (Sweden)

    Geissel H.

    2014-03-01

    Full Text Available Precision experiments with relativistic fragments separated in-flight require special experimentalmethods to overcome the inherent large emittance from the creation in nuclear reactions and atomic interactions in matter. At GSI relativistic exotic nuclei have been produced via uranium projectile fragmentation and fission and investigated with the inflight separator FRS directly, or in combination with either the storage-cooler ring ESR or the FRS Ion Catcher. 1000 A·MeV 238U ions were used to create 60 new neutron-rich isotopes separated and identified with the FRS to measure their production cross sections. In another experimental campaign the fragments were separated in flight and injected into the storage-cooler ring ESR for accurate mass and lifetime measurements. In these experimentswe have obtained accurate new mass values analyzed via a novel method which has reduced the systematic errors for both Schottky Mass Spectrometry (SMS and for Isochronous Mass Spectrometry (IMS. Pioneering experiments have been carried out with the FRS Ion Catcher consisting of three experimental components, the dispersive magnetic system of the FRS with a monoenergetic and a homogeneous degrader, a cryogenic stopping cell filled with pure helium and a multiple-reflection time-of flight mass separator. The FRS Ion Catcher enables high precision spectroscopy experiments with eV to keV exotic nuclides. Results from these different FRS experiments are presented in this overview together with prospects for the next-generation facility Super-FRS. The novel features of the Super-FRS compared with the present FRS will be discussed in addition.

  19. Recent Precision Experiments with Exotic Nuclei Produced with Uranium Projectiles and Experimental Prospects at Fair

    Science.gov (United States)

    Geissel, H.; Chen, L.; Dickel, T.; Farinon, F.; Dillmann, I.; Knöbel, R.; Kurcewicz, J.; Mukha, I.; Münzenberg, G.; Nociforo, C.; Patyk, Z.; Pietri, S.; Plass, W. R.; Prochazka, A.; Scheidenberger, C.; Takechi, M.; Weick, H.; Winfield, J. S.; Winkler, M.

    2014-03-01

    Precision experiments with relativistic fragments separated in-flight require special experimentalmethods to overcome the inherent large emittance from the creation in nuclear reactions and atomic interactions in matter. At GSI relativistic exotic nuclei have been produced via uranium projectile fragmentation and fission and investigated with the inflight separator FRS directly, or in combination with either the storage-cooler ring ESR or the FRS Ion Catcher. 1000 A·MeV 238U ions were used to create 60 new neutron-rich isotopes separated and identified with the FRS to measure their production cross sections. In another experimental campaign the fragments were separated in flight and injected into the storage-cooler ring ESR for accurate mass and lifetime measurements. In these experimentswe have obtained accurate new mass values analyzed via a novel method which has reduced the systematic errors for both Schottky Mass Spectrometry (SMS) and for Isochronous Mass Spectrometry (IMS). Pioneering experiments have been carried out with the FRS Ion Catcher consisting of three experimental components, the dispersive magnetic system of the FRS with a monoenergetic and a homogeneous degrader, a cryogenic stopping cell filled with pure helium and a multiple-reflection time-of flight mass separator. The FRS Ion Catcher enables high precision spectroscopy experiments with eV to keV exotic nuclides. Results from these different FRS experiments are presented in this overview together with prospects for the next-generation facility Super-FRS. The novel features of the Super-FRS compared with the present FRS will be discussed in addition.

  20. Elastic break-up of 156 MeV 6Li projectiles with large asymptotic relative momenta of the fragments

    International Nuclear Information System (INIS)

    The triple differential cross sections for elastic break-up of 156 MeV 6Li projectiles by the reactions 208Pb (6Li, ad) 208Pbg.s., and 12C (6Li, ad) 12Cg.s. have been measured with large asymptotic relative momenta of the outgoing fragments. The data exhibit rather unfamiliar shapes of the energy spectra, often replacing the usual bell-shape distributions by double-peaked structures and varying rapidly with the relative emission angles. The origin of these features has been explored and the cross sections have been analysed on the basis of a diffractive disintegration approach. (orig.)

  1. Damage production in low-energy Au and Si irradiation of a-Si: Influence of projectile mass

    CERN Document Server

    Koster, M

    2003-01-01

    Using molecular-dynamics computer simulation, we study the processes occurring in a-Si after irradiation with a projectile with energy E sub 0<=500 eV. By comparing Au and Si impact, we can study the effects of high and low deposited energy density. We find that damage production (creation of over- and under-coordinated Si atoms) and recoil implantation are strongly enhanced under Au impact. This effect can be traced back to the creation of an elastic collision spike for Au impact.

  2. Projectile- and charge-state-dependent electron yields from ion penetration of solids as a probe of preequilibrium stopping power

    DEFF Research Database (Denmark)

    Rothard, H.; Schou, Jørgen; Groeneveld, K.-O.

    1992-01-01

    Kinetic electron-emission yields gamma from swift ion penetration of solids are proportional to the (electronic) stopping power gamma approximately Beta-S*, if the preequilibrium evolution of the charge and excitation states of the positively charged ions is taken into account. We show that the...... theory after having presented a summary of recent results on the projectile- and charge-state dependence of forward and backward electron yields gamma(F) and gamma(B) and the Meckbach factor R = gamma(F)/gamma(B). A simple extension of the yield equations is proposed and several assumptions are justified...

  3. Geometrical aspects of reaction cross sections for {sup 3}He, {sup 4}He and {sup 12}C projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Ingemarsson, A. [Uppsala Univ. (Sweden). Dept. of Radiation Sciences; Lantz, M. [Uppsala Univ. (Sweden). The Svedberg Laboratory

    2003-04-01

    A black-disc model combined with accurate matter densities has been used for an investigation of reaction cross sections for {sup 3}He, {sup 4}He and {sup 12}C projectiles. A simple relation is derived between the energy dependence of the reaction cross sections and the strength of the nucleon-nucleon interaction. A comparison is also made of the reaction cross sections for {sup 3}He and {sup 4}He for six different nuclei {sup 12}C, {sup 16}O, {sup 40}Ca, {sup 58,60}Ni and {sup 208}Pb.

  4. Very forward studies of projectile-like fragments by using a telescopic mode of a double spectrometer

    International Nuclear Information System (INIS)

    On the tenth anniversary of projectile fragmentation, the question of the real occurrence of this process at the GANIL energies seems to be still open. At first, we will see the importance of doing complete angular distribution including very forward measurements in the study of the fragmentation process. Then, a new type of use of a double spectrometer will be presented and the possibility to get precise angular measurements at and around O0, even at very small excitation energies, will be demonstrated. At last, some results obtained at O0 will be compared to grazing angle measurements

  5. Neutron-rich rare isotope production from projectile fission of heavy beams in the energy range of 20 MeV/nucleon

    CERN Document Server

    Vonta, N; Loveland, W D; Kwon, Y K; Tshoo, K; Jeong, S C; Veselsky, M; Bonasera, A; Botvina, A

    2016-01-01

    We investigate the possibilities of producing neutron-rich nuclides in projectile fission of heavy beams in the energy range of 20 MeV/nucleon expected from low-energy facilities. We report our efforts to theoretically describe the reaction mechanism of projectile fission following a multinucleon transfer collision at this energy range. Our calculations are mainly based on a two-step approach: the dynamical stage of the collision is described with either the phenomenological Deep-Inelastic Transfer model (DIT), or with the microscopic Constrained Molecular Dynamics model (CoMD). The deexcitation/fission of the hot heavy projectile fragments is performed with the Statistical Mul- tifragmentation Model (SMM). We compared our model calculations with our previous experimental projectile-fission data of 238U (20 MeV/nucleon)+208Pb and 197Au (20 MeV/nucleon)+197Au and found an overall reasonable agreement. Our study suggests that projectile fission following periph- eral heavy-ion collisions at this energy range of...

  6. Measurement of Low Level Explosives Reaction in Gauged Multi-Dimensional Steven Impact Tests

    Energy Technology Data Exchange (ETDEWEB)

    Niles, A M; Garcia, F; Greenwood, D W; Forbes, J W; Tarver, C M; Chidester, S K; Garza, R G; Swizter, L L

    2001-05-31

    The Steven Test was developed to determine relative impact sensitivity of metal encased solid high explosives and also be amenable to two-dimensional modeling. Low level reaction thresholds occur at impact velocities below those required for shock initiation. To assist in understanding this test, multi-dimensional gauge techniques utilizing carbon foil and carbon resistor gauges were used to measure pressure and event times. Carbon resistor gauges indicated late time low level reactions 200-540 {micro}s after projectile impact, creating 0.39-2.00 kb peak shocks centered in PBX 9501 explosives discs and a 0.60 kb peak shock in a LX-04 disk. Steven Test modeling results, based on ignition and growth criteria, are presented for two PBX 9501 scenarios: one with projectile impact velocity just under threshold (51 m/s) and one with projectile impact velocity just over threshold (55 m/s). Modeling results are presented and compared to experimental data.

  7. The study of quasi-projectiles produced in Ni+Ni and Ni+Au collisions: excitation energy and spin; Etude des quasi-projectiles produits dans les collisions Ni+Ni et Ni+Au: energie d'excitation et spin

    Energy Technology Data Exchange (ETDEWEB)

    Buta, A

    2003-02-01

    During the collision between the projectile and the target nuclei in the intermediate energy regime (E < 100 MeV/nucleon) two excited nuclei are mainly observed in the exit channel, the quasi projectile (QP) and the quasi target. They disintegrate by particle emission. However, this binary picture is perturbed by the emission of particles and light fragments with velocities intermediate between the projectile velocity and the target one, all along the interaction (midrapidity component). This work aim to determine the excitation energy and the intrinsic angular momentum (or spin) of quasi-projectiles produced in the Ni+Ni and Ni+Au collisions at 52 and 90 MeV/nucleon. The excitation energy is deduced from the kinematical characteristics of particles emitted by the quasi-projectile. They have to be separated from midrapidity particles. Three different scenarios have been used for this purpose. The spin of the quasi-projectile has been extracted from the experimental data by mean of proton and alpha particles multiplicities emitted by the QP in the Ni+Au at 52 MeV/nucleon reaction. The results have been compared to the predictions of a theoretical model based on nucleon transfers. Their evolution is qualitatively reproduced as a function of the violence of the collision. (author)

  8. Importance of vacancy cascades in argon recoil-ion charge-state distributions accompanied by coincident projectile-electron capture and loss

    International Nuclear Information System (INIS)

    Argon recoil-ion charge-state distributions produced by beams of 0.7-MeV/u Cl/sup 5+,8+,10+/ have been measured by time-of-flight (TOF) techniques in coincidence with single- and double-charge-changed projectiles. In an essential improvement to the usual multinomial description of ionization in the independent-electron-ejection model, we find that inclusion of one (two) Auger vacancy cascades significantly alters the description of the recoil-ion spectra corresponding to single (double) capture. The single- and double-projectile-electron loss and capture spectra strongly resemble each other, suggesting that loss of one or two projectile electrons is closely associated with loss of one or two target L electrons, respectively. These conclusions are consistent with impact parameters inferred from determinations of mean recoil energy

  9. The prediction of non-compound nucleus fission contribution as a function of the mass number of projectile to induced fission of Pb nucleus

    Directory of Open Access Journals (Sweden)

    S Soheyli

    2013-03-01

    Full Text Available  The recent investigations show that the size and mass number of the target nucleus in the heavy-ion fission reactions are very important for the angular distribution of fission fragments. In this work, we consider the behavior of fission fragment angular anisotropies within the standard saddle-point statistical model for the 168O, 188O, 199F, 2412Mg, 2814Si, 32 16 S+20882Pb fission reaction systems. As a result, a relation is found between the average contribution of non-compound nucleus fission and the mass number of projectile for these systems. It is also obtained that the onset of this contribution is significant for the projectile with the mass number greater than 20, as well as this quantity is an increasing function of the mass number of projectile. Finally, the comparison condition between α, and α BG is modified for these reaction systems.

  10. Rate capability of a cryogenic stopping cell for uranium projectile fragments produced at 1000 MeV/u

    Science.gov (United States)

    Reiter, M. P.; Rink, A.-K.; Dickel, T.; Haettner, E.; Heiße, F.; Plaß, W. R.; Purushothaman, S.; Amjad, F.; Ayet San Andrés, S.; Bergmann, J.; Blum, D.; Dendooven, P.; Diwisch, M.; Ebert, J.; Geissel, H.; Greiner, F.; Hornung, C.; Jesch, C.; Kalantar-Nayestanaki, N.; Knöbel, R.; Lang, J.; Lippert, W.; Miskun, I.; Moore, I. D.; Nociforo, C.; Petrick, M.; Pietri, S.; Pfützner, M.; Pohjalainen, I.; Prochazka, A.; Scheidenberger, C.; Takechi, M.; Tanaka, Y. K.; Weick, H.; Winfield, J. S.; Xu, X.

    2016-06-01

    At the Low-Energy Branch (LEB) of the Super-FRS at FAIR, projectile and fission fragments will be produced at relativistic energies, separated in-flight, energy-bunched, slowed down and thermalized in a cryogenic stopping cell (CSC) filled with ultra-pure He gas. The fragments are extracted from the stopping cell using a combination of DC and RF electric fields and gas flow. A prototype CSC for the LEB has been developed and successfully commissioned at the FRS Ion Catcher at GSI. Ionization of He buffer gas atoms during the stopping of energetic ions creates a region of high space charge in the stopping cell. The space charge decreases the extraction efficiency of stopping cells since the high amount of charge distorts the applied DC electric drag fields. Thus the understanding of space charge effects is of great importance to make full use of the high yields at future RIB facilities such as the Super-FRS at FAIR. For this purpose a detailed study of space charge effects in the CSC was performed using experiments and simulations. The dependence of the extraction efficiency, the extraction time and the temporal ion extraction profile on the intensity of the impinging beam and the electric field strength was studied for two different 238 U projectile fragments produced at 1000 MeV/u and separated with the FRS. Good agreement between experiments and simulations was found.

  11. Interactions of $^{16}$O Projectile and its Fragments in Nuclear Emulsion at about 60 and 200 GeV/nucleon

    CERN Multimedia

    2002-01-01

    The aim of the experiment is to measure the multiplicity ``$ n _{s} $'' and pseudo-rapidity ``$\\eta$'' of the shower particles ($\\beta$~$\\geq$~0.7) produced in different types of collisions (peripheral, semi-central and central), of $^{16}$O and $^{32}$S in nuclear emulsions. The multiplicities and angular distributions of both the grey ``$ n _{g} $'' (mainly due to knock- on and recoil protons), and black ``$ n _{b} $'' (slow evaporated target fragments) particles, and the inter-correlation between them are studied. \\\\ \\\\ The yield, charge and angular distributions of produced relativistic projectile fragments P.F.S., for $ Z _{P} . _{F} . $ $\\geq$~2 are measured and their interactions in emulsions are investigated. \\\\ \\\\ The study of the mean free paths for the projectile fragments with Z $\\geq$ 3 produced from 200~A~GeV $^{16}$ 0 interactions were performed, which show the absence of the anomalous phenomena. \\\\ \\\\ The possible production of zero-spin light neutral scaler bosons and pseudoscaler bosons from...

  12. Atom and molecule projectile and fast aggregate excitation, ionization and dissociation in thin targets in the out-of-charge equilibrium field

    International Nuclear Information System (INIS)

    The aim of this experimental study is to confirm the possible existence of bound states for light atomic and molecular projectiles inside solid targets, in the MeV energy range. For this purpose we have used, various experimental methods such as charge state distribution measurements, energy loss measurements, beam foil spectroscopy and electron spectroscopy. It was confirmed that bound states of light atomic and molecular projectiles can exist in a solid medium. The various cross sections (charge exchange, excitation, ionisation, dissociation) relative to these bound states have been measured

  13. Systematic study of projectile fragments in nucleus-nucleus collisions at 4.1-4.5 A GeV/c and multi-source thermal model

    Energy Technology Data Exchange (ETDEWEB)

    Rahim, M.A.; Fakhraddin, S.; Asharabi, H. [Sana' a University, Physics Department, Faculty of Science, Sana' a (Yemen)

    2012-08-15

    The multiplicity distributions of projectile fragments (PFs) produced in interactions of ({sup 4}He, {sup 12}C, {sup 16}O, {sup 22}Ne and {sup 28}Si) with emulsion (Em) at 4.1-4.5 A GeV/c beam energies, and their dependence on target groups (H, CNO and AgBr) are presented and have been reproduced by using a multi-source thermal model. The dependence of the mean multiplicities on masses of projectile and target nuclei is investigated. The experimental results are compared with the corresponding ones from the theoretically calculated ones. The experimental results agree with theoretical calculations using the multi-source thermal model. (orig.)

  14. Correlations between projectile-like and target-like fragments in the reaction 40Ar+natAg at 60 MeV/nucleon

    International Nuclear Information System (INIS)

    Velocity, mass and angular correlations between projectile-like and target-like fragments have been measured in the 40Ar+Ag reaction at 60 MeV/u. With respect to similar data taken at 30 MeV/u, important deviation are observed in the mass correlation. A calculation assuming a binary process in which, before decaying, the projectile and the target are excited by stochastic exchange of nucleons seems to give a better agreement with the data than predictions based on the partipant-spectator model

  15. Role of nucleon-nucleon collisions in peripheral nuclear reactions near 30 MeV/A. Study of neutrons/projectile-like fragment correlations in the 20Ne + 165Ho reaction at 30 MeV/A

    International Nuclear Information System (INIS)

    Correlations between projectile-like fragments (4 ≤ Z 20Ne + 165Ho reaction at 30 MeV/A have been measured. Projectile-like fragments emitted at ± 80 were detected with two silicon detectors. Coincident neutrons were detected with 10 NE213 scintillators set between -1400 and +1400. Projectile-like fragment energy spectra and neutron velocity and multiplicity distributions were thus obtained. As a function of the charge and energy of the projectile-like fragment, neutron velocity spectra were analysed using three moving sources: a projectile-like source, a target-like source and an intermediate velocity source. Experimental results were compared with predictions of a statistical model, based on nucleon-nucleon collisions (code PERCUT), the de-excitation of primary products being treated by statistical evaporation models (codes LANCELOT and EVAP). For low linear momentum transfer collisions, experimental results are in good agreement with theoretical predictions

  16. Ion desorption phenomena induced by various types of multiply charged projectiles and by photons on solid surfaces

    International Nuclear Information System (INIS)

    Ion desorption experiments are described in two regions of primary ion velocities corresponding to two distinct classes of interaction mechanism. At low speeds, atomic collisions take place, at higher speeds than the electron velocity, electronic collisions occur. Experiments with fast ions above 0.2 MeV/u are described, using 32S and 235U ions obtained in a cyclotron and a linear accelerator. Emission of H+ ions from solid surfaces is measured and analyzed, and applied to the determination of the charge state of a fast ion in a solid. Experiments using single atomic and polyatomic, keV ions, and organic and CsI cluster ions as projectiles are also presented. Finally, laser desorption is discussed. (R.P.) 81 refs., 27 figs., 2 tabs

  17. Coincidence cross sections within the quasi free break-up model for elastic projectile break-up

    International Nuclear Information System (INIS)

    Scrutinizing the basic break-up model of Serber we show that it is possible to derive the triple differential cross sections for particle-particle coincidences in analytical form. An alternative interpretation within the opaque version of the model suggests to assign these cross sections to the elastic nonresonant projectile break-up due to the nuclear interaction. Distortion effects by the Coulomb field of the target are included in analogy to the Serber model. Beside the well known single maximum in the break-up spectra double and triple peak structures appear for certain combinations of the observation angles. The model yields reasonable agreement to the given experimental data, concerning the multiple peak structure as well as the order of magnitude for the absolute normalisation. Its application comprises the region of forward emission angles, especially the angular range of the classical Coulomb deflection. (orig.)

  18. K-vacancy production in heavy-ion collisions. I. Experimental results for Z > or = 35 projectiles

    International Nuclear Information System (INIS)

    We have determined projectile and target K x-ray cross sections from a variety of targets spanning the periodic table and bombarded by 12--60-MeV Br, 200--330-MeV Kr, 15--80-MeV I, 326--470-MeV Xe, and 90--110-MeV Pb. Most targets were thick solids, but, to assure proper extraction of cross sections, some thin solid and gas targets have also been used. The present paper mainly gives experimental details and describes the method of cross-section determination. In subsequent papers various features of the target dependence of the cross section are to be examined in terms of atomic and molecular models of inner-shell excitation processes

  19. Measurements in the beam direction of the 40Ar projectile fragmentation at 44 MeV/A

    International Nuclear Information System (INIS)

    Accurate beam direction measurements (0±3mr) have been performed on the 40Ar projectile fragmentation on a Ni target, at 44 MeV/u, by using the telescopic mode on the double spectrometer LISE at GANIL. Sampling results on Al and Au targets are also presented. Velocity distributions are analysed for fragments of masses from 10 to 45. As expected from a study of the forward angle physics, the presented beam direction measurements (0 deg) and the grazing angle ones (3 deg) exhibit spectacular differences. The most probable velocities are found much closer to the beam one at 0 deg than at 3 deg. The velocity-integrated mass-yields obtained in the beam direction exhibit a regular exponential rise from A ∼ 18 to A ∼ 40. The role of diffraction is to be examined. (author) 24 refs., 13 figs., 2 tabs

  20. Deuteron - $\\alpha$ interaction by inversion of RGM S-matrix determination of spin-orbit potential for spin-1 projectile

    CERN Document Server

    MacIntosh, R S

    1997-01-01

    The iterative-perturbative (IP) procedure for S-matrix to potential inversion is applied to spin-one projectiles for the restricted case of vector spin-orbit interaction only. In order to evaluate this extension of IP inversion we have inverted the multi-channel RGM $S_{lj}$ of Kanada et al for deuterons scattering from $^4$He with deuteron distortion and then compared the central components with those derived from RGM with spin set to zero. Attention is given to the question of how well the resulting potentials are established. Reliable spin-1 inversion is demonstrated. Results relating to inversion, to deuteron-nucleus interactions and to RGM are presented and suggest the range of nuclear interaction information which the procedure makes possible. Unusual non-locality and parity dependence effects are found; these are of possible relevance to generic properties of nuclear potentials.

  1. The unified description of direct and resonant excitations of the nucleus 40Ca by medium-energy projectiles

    International Nuclear Information System (INIS)

    In the framework of a unified theory of direct and resonant reactions the excitation of 40Ca by medium-energy projectiles has been investigated. The applied 1p-1h approximation turns out to be capable of describing the gross features of the measured spectra. A considerable part of the smooth background is found to be produced by resonance transitions. A dominant g/sub 9/2/(1d/sub 5/2/)-1 structure of the giant quadrupole resonance is proposed, which is in agreement with the observed decay channels. The importance of high-lying single-particle states with large angular momentum 1 > 3 is emphasized, in particular for reactions with hadrons. It is shown that coincidence experiments are suitable for suppressing the background. (author)

  2. Precision Measurement of the Hyperfine Structure of Laser-Cooled Radioactive 7Be+ Ions Produced by Projectile Fragmentation

    International Nuclear Information System (INIS)

    The ground state hyperfine splitting of 7Be+ has been measured by laser-microwave double-resonance spectroscopy in the online rf trap of RIKEN's slow RI-beam facility. Be ions produced by projectile fragmentation of 13C at ≅1 GeV were thermalized in a rf ion guide gas cell and subsequently laser cooled in the ion trap to ≅1 μeV. This 1015-fold reduction of the kinetic energy allows precision spectroscopy of these ions. A magnetic hfs constant of A=-742.772 28(43) MHz was measured for 7Be+, from which a nuclear magnetic moment of μI=-1.399 28(2)μN was deduced

  3. Projectile energy dependence in the molecular excitation of th H3+, D3+ molecular ions in their polar dissociation

    Energy Technology Data Exchange (ETDEWEB)

    Yousif, F.B.; Hinojosa, G.; Dominguez, I. [IFUNAM, Cuernavaca (Mexico)] [and others

    1996-05-01

    The laboratory energy distributions of H{sup +} and D{sup +} in coincidence with H{sup {minus}} and D{sup {minus}} ions, resulting from the collision-induced-dissociation of H{sup 3+} and D{sup 3+} on He target for incoming beam energies ranging from 2.5 to 9.0 keV has been measured. The energy-analyzed-spectra of ionic fragments were measured both independently and in coincidence with each other. From these, the energy absorbed by the dissociating molecular ions in the excitation process induced by the collision with He prior to its breakup, was evaluated as a function of the projectile energy and it was found that it is not constant but it is consistent with the identified H{sup 3+} excited states which have adiabatic Born-Oppenheimer energies of 21-50 eV above the H{sup 3+} ground state.

  4. Projectile energy dependence in the molecular excitation of th H3+, D3+ molecular ions in their polar dissociation

    International Nuclear Information System (INIS)

    The laboratory energy distributions of H+ and D+ in coincidence with H- and D- ions, resulting from the collision-induced-dissociation of H3+ and D3+ on He target for incoming beam energies ranging from 2.5 to 9.0 keV has been measured. The energy-analyzed-spectra of ionic fragments were measured both independently and in coincidence with each other. From these, the energy absorbed by the dissociating molecular ions in the excitation process induced by the collision with He prior to its breakup, was evaluated as a function of the projectile energy and it was found that it is not constant but it is consistent with the identified H3+ excited states which have adiabatic Born-Oppenheimer energies of 21-50 eV above the H3+ ground state

  5. Influence of the neutron numbers of projectile and target on the evaporation residue cross sections in hot fusion reactions

    Science.gov (United States)

    Zhu, Long; Su, Jun; Zhang, Feng-Shou

    2016-06-01

    Within the framework of a dinuclear system model, the influence of projectile and target neutron number on capture cross section, fusion probability, and survival probability for the reactions S,3634+238U and 48Ca+Pu 239 ,240 ,242 ,244 are investigated. The calculated excitation functions are in good agreement with the experimental data. To synthesize more unknown neutron-deficient isotopes of already-known superheavy elements, the possibility of using lighter calcium isotopes to induce hot fusion reactions is investigated and the maximal evaporation residual cross sections for Ca 44 ,46 ,48 -induced hot fusion reactions to produce unknown neutron-deficient superheavy nuclei with Z =112 -116 are predicted.

  6. Subthreshold pion production of 20-100 MeV energy with various projectiles (p, 3He, 12C, 16O)

    International Nuclear Information System (INIS)

    The described experiments refer to pion production below and near the threshold with different projectiles (p, 3He, 12C, 16O). The pion detection device was a range telescope. Experimental methods are presented and discussed. Data are compared to predictions of some models

  7. Centrifuge and laboratory tests, modelling the penetrator concept for the disposal of HGW in deep ocean sediments

    International Nuclear Information System (INIS)

    The report is a summary of the work carried out at Cambridge University Engineering Department to investigate the geotechnical aspects of the subseabed disposal of heat generating waste. The problem of heat transfer and coupled consolidation around a heat source was studied both experimentally and numerically. Calculations of the temperature and pore pressure changes in the soil around a cylindrical heat source were made and verified by both laboratory tests and by centrifuge modelling at 100 times earth's gravity. It was shown that conduction was the major heat transfer process. The high velocity penetration of soil by projectiles was modelled on the Cambridge Geotechnical Centrifuge and this was followed by centrifuge tests in which there was subsequent heating of the projectile after firing. These dynamic tests showed that the projectile produced high pore pressures within the soil, which were quickly dissipated. (author)

  8. Rocket Projectile Detection Information Analysis System%火箭弹检测信息分析系统

    Institute of Scientific and Technical Information of China (English)

    范志锋; 崔平; 文健; 徐敬青

    2014-01-01

    In allusion to the problem of using detection information of factory and army past years to receive the variation law of the control system electrical capability of a type of rocket projectile, developing a rocket projectile detection information analysis system based on mixed programming of PB/Matlab/SQL Server/Excellis put forward. Overall function, development tools and technology and design of development function module of the system are introduced. Some basically sport technique segments of design and implementation of the system are mainly explained and the main characteristics of the system are analyzed. It is shown by the application that the system has virtues of good interface, universality, operability and easy to maintain. The system has solved the problems of management, analysis and plotting of mass detection information.%针对利用出厂检测信息和部队历年检测信息得到火箭弹控制系统电性能变化规律存在的难题,提出基于PB/Matlab/SQL Server/Excel 混合编程开发火箭弹检测信息分析系统。介绍系统总体功能、开发工具与技术、开发功能模块设计,重点对系统开发与实现的一些主要技术环节进行说明,并分析系统主要特点。应用结果表明:该系统界面友好,通用性、可操作性强,易于维护,能高效解决海量检测信息管理、分析和绘图等问题。

  9. Clovis Age Western Stemmed Projectile Points and Human Coprolites at the Paisley Caves

    DEFF Research Database (Denmark)

    Jenkins, D.L.; Davis, Loren G.; Stafford Jr., T.W.;

    2012-01-01

    technological evolution. "Blind testing" analysis of coprolites by an independent laboratory confirms the presence of human DNA in specimens of pre-Clovis age. The colonization of the Americas involved multiple technologically divergent, and possibly genetically divergent, founding groups....

  10. Ballistic behavior of high hardness perforated armor plates against 7.62 mm armor piercing projectile

    International Nuclear Information System (INIS)

    Highlights: • High hardness perforated plates can be used effectively in ballistic protection. • Perforated plate has potential of decreasing areal mass efficiency dramatically. • The defeating mechanism of multilayer perforated plates includes three principles. • Deviation from trajectory, core fracture and nose erosion are defeating mechanisms. • With the simulations and tests, the bullet defeating mechanism has been explained. - Abstract: In this paper, some of the important defeating mechanisms of the high hardness perforated plates against 7.62 × 54 armor piercing ammunition were investigated. The experimental and numerical results identified three defeating mechanisms effective on perforated armor plates which are the asymmetric forces deviates the bullet from its incident trajectory, the bullet core fracture and the bullet core nose erosion. The initial tests were performed on the monolithic armor plates of 9 and 20 mm thickness to verify the fidelity of the simulation and material model parameters. The stochastic nature of the ballistic tests on perforated armor plates was analyzed based on the bullet impact zone with respect to holes. Various scenarios including without and with bullet failure models were further investigated to determine the mechanisms of the bullet failure. The agreement between numerical and experimental results had significantly increased with including the bullet failure criterion and the bullet nose erosion threshold into the simulation. As shown in results, good agreement between Ls-Dyna simulations and experimental data was achieved and the defeating mechanism of perforated plates was clearly demonstrated

  11. Ballistic Performance of Coconut Shell Powder/Twaron Fabricagainst Non-armour Piercing Projectiles

    Directory of Open Access Journals (Sweden)

    M.S. Risby

    2008-03-01

    Full Text Available Body armour technologists over the years are seeking to develop protective systems whichare both effective and lightweight. However these hard armour materials are very expensive andhave certain weight constraints. From this point of view, natural fibres and fillers have attractedthe attention of researchers due to their low density with high specific strengths, abundance,availability, renewability and being environmental-friendly. This paper reports the potential useof coconut shell powder-epoxy composite (COEX panel bonded with Twaron CT716 fabric asa hard armour material and the characteristics of its fracture imprints from a specific threat levelwhen subjected to ballistic tests1 (NIJ Standard 0108.01. It was observed that the imprint patternson the particulate composite (COEX could be identified according to effectiveness in impactenergy dissipation. COEX/Twaron test panel was found to withstand impact equivalent to NIJLevel IIIA using 9 mm FMJ ammunition but perforated at NIJ Level III of 7.62 mm FMJ bulletimpacts. Test results showed that COEX panel do possess shock absorbance characteristics andcan be utilised as  an armour component in the hard-body armour system. Dependency onTwaron fabric layers as ballistic reinforcements has been reduced up to 3-time with 170 per centimprovement on energy-absorption capabilities when using COEX composite as the frontalcomponent of the armour.

  12. Fragmentation of nuclei as a function of centrality of collision in interactions of gold projectiles at 10.6 A GeV

    CERN Document Server

    Dabrowska, A; Olszewski, A; Szarska, M; Trzupek, A; Wilczynska, B; Wilczynski, H; Wolter, W; Wosiek, B; Wozniak, K

    2001-01-01

    We have studied the fragmentation of light (C/N/O) and heavy (Ag/Br) nuclei of emulsion in collisions with gold projectiles at 10.6 A GeV and the fragmentation of these gold nuclei in collisions with hydrogen, (C/N/O) and (Ag/Br) nuclei. The analysis was restricted to the investigation of the number of fragments and in some cases the total charge of fragments as a function of the centrality of collisions with nuclei of different masses. We observe a decrease in the number of target fragments with increasing centrality for interactions of projectiles with masses comparable or greater than the mass of the target nucleus. As the collision becomes more central a significant number of participating protons from the target nucleus get enough momentum to become relativistic due to intranuclear interactions. These results have been compared with the predictions of the RQMD model.

  13. Saturation effect in projectile- and target- x-ray production in collisions between 2.5 MeV/u highly charged Cu ions and gaseous targets

    Science.gov (United States)

    Kumar, Ajay; Misra, D.; Kelkar, A. H.; Kadhane, U.; Singh, Y. P.; Lapicki, G.; Gulyas, L.; Tribedi, L. C.

    2006-01-01

    L x-ray production cross sections have been measured for highly charged 2.5 MeV/u Cuq+ (q = 20-26) ions colliding with H2, Ne, Ar, Kr and Xe target atoms. The observed Cu L x-rays are due to the excitation and electron-transfer processes. The charge state dependence of the projectile L x-rays has been studied with Ar and Kr targets. We have derived the subshell resolved K-L1, K-L2 and K-L3 electron-transfer cross sections from the measured Ar K x-ray yields as a function of L vacancies in Cu ion. The measured projectile L x-ray production cross sections arising from the excitation and electron capture are found to saturate as target atomic number Zt increases. Similarly, a saturation has also been found in the Ar K-shell ionization cross sections as a function of Zp.

  14. Adiabatic and sudden interaction potentials in the fusion-fission of heavy ion collisions: Asymmetric target-projectile combinations

    International Nuclear Information System (INIS)

    It is now well known that many reactions giving measurable fusion cross-sections also show a fission of the compound system formed, similar to the low energy fission of the known fissioning nuclei. Recently, both the fusion excitation functions and the mass equilibration in the fragmentation of the composite system were measured for a large number of systems with 94208Pb on different targets of 26Mg, 48Ca, 50Ti, 52Cr, 58Fe and 64Ni. From a theoretical point of view, it is relevant to ask the question: how do the colliding nuclei fuse and then why does the compound system formed fission instead of going to the ground state to give a stable system. In this Letter, we attempt to show that the fusion of asymmetric colliding nuclei is due to the overcoming of the interaction barriers in adiabatic potentials and the fission of the compound system should perhaps occur as a sudden process, like the one in the spontaneous fission phenomenon. We have made our calculations for the compound systems with 102<=Z<=110 and for the asymmetric target-projectile combinations of the experiments of Ref. 1, using the fragmentation theory whose basis is the asymmetric two-centre shell model

  15. Internal electron emission detected in metal-insulator-metal thin film tunnel devices bombarded with keV cluster projectiles

    International Nuclear Information System (INIS)

    The electronic excitation of a solid surface bombarded by energetic ions manifests in the production of hot electrons, which can be either emitted from the surface (''kinetic electron emission'') or remain within the solid. We use Metal-Insulator-Metal (MIM) tunneling junctions to detect and investigate hot charge carriers (electrons and holes) produced during bombardment of a metal surface with keV rare gas (Ar+) ions. The sample consists of a top metal film of about 20 nm thickness (the actual bombarded target surface), an underlying thin (2-3 nm) oxide film deposited and another metal electrode underneath. With such a device, excitations below the vacuum level can be detected as an internal electron emission current between the two metal electrodes. By combining the information obtained from external and internal emission, it is possible to gain information regarding the depth distribution of the generated excitation as well as the transport mechanism distributing the excitation away from its initial point of generation. We demonstrate this by varying the impact angle of the projectile ion beam. It is found that external and internal emission currents vary exactly in opposite direction when going from normal to oblique incidence.

  16. Study of 84Kr36 projectile fragments with compound multiplicity at ∼1 A GeV

    International Nuclear Information System (INIS)

    Nuclear emulsion detector (NED) has had a very long track record as particle detector and its importance has been proven through a long list of fundamental discoveries. It consists of H, CNO and silver halides (AgBr), where a latent track is formed after the passage of an ionizing particle. In the nuclear emulsion heavy ion collisions at intermediate and high energies provide to study the properties of nuclear dense matter and extreme conditions. In the last few decades, pions, kaons and recoil nucleons were the focus of the study of hadron-nucleus and nucleus-nucleus collision. These recoil target's nucleons (Grey particles) are in the medium energy (30-400 MeV), and basically these are eject-out target protons and emitted during the passage of leading particles. In the hadron-nucleus and nucleus-nucleus collision at higher energy, the new variable term introduced NC (= Ng + Ns) that is compound multiplicity. NC was introduced by Jurak and Linsheid, which represents the complete participant region of the colliding nucleus. Our earlier study of participants region with target's fragmentation and their dependency on the energy of the colliding system showed strong dependency on both parameters. Therefore it is important to study the participant region in the light of projectile fragmentation

  17. Optical model parallel description of elastic, fusion and breakup cross sections for systems with weakly bound projectiles

    Science.gov (United States)

    Gómez Camacho, A.; Gomes, P. R. S.; Lubian, J.; Aguilera, E. F.

    2014-03-01

    A brief description is presented of the results obtained in recent years for the simultaneous analysis of elastic and fusion cross section data of nuclear reactions for several nuclear systems with weakly bound and halo projectiles. The method used in this description, consists of simultaneously determine the parameters of fusion UF and direct reaction UDR polarization potentials of Woods-Saxon geometric shapes, that fit the elastic and fusion data. As a matter of fact, UFis an energy dependent potential, with real VF and imaginary WFcomponents, that is responsible for fusion reactions. Similarly, UDR is also energy dependent with real VDR and imaginary WDR parts, that accounts for direct reactions. A general finding for all the systems presented is that, the real and imaginary parts of the fusion potential and direct reaction potentials, are related by a dispersion relation and their energy dependence around and below the Coulomb barrier, show the so-called Breakup Threshold Anomaly. The effect of breakup reactions on fusion cross sections is studied by analyzing the separate effect of the absorption potential WDR and the fusion barrier rising produced by VDR.

  18. In–out asymmetry in the interaction of a charged projectile traversing a vacuum–metal interface in an oblique trajectory

    Energy Technology Data Exchange (ETDEWEB)

    Gervasoni, J.L. [Centro Atómico Bariloche (Comisión Nacional de Energía Atómica), R8402AGP S. C. de Bariloche, Río Negro (Argentina); Instituto Balseiro (Universidad Nacional de Cuyo and Comisión Nacional de Energía Atómica), R8402AGP S. C. de Bariloche, Río Negro (Argentina); Segui, S. [Centro Atómico Bariloche (Comisión Nacional de Energía Atómica), R8402AGP S. C. de Bariloche, Río Negro (Argentina); Barrachina, R.O. [Centro Atómico Bariloche (Comisión Nacional de Energía Atómica), R8402AGP S. C. de Bariloche, Río Negro (Argentina); Instituto Balseiro (Universidad Nacional de Cuyo and Comisión Nacional de Energía Atómica), R8402AGP S. C. de Bariloche, Río Negro (Argentina)

    2015-07-01

    In this work, we analyze the interaction of moving charged particles with plasmons in a semi-infinite material. For planar surfaces, and in the frame of a semiclassical dielectric formulation, we analyze the differences and similarities that arise when we compare incoming and outgoing trajectories in oblique incidence. We describe an oscillatory structure that only appears in the bulk contribution to the energy lost by an incoming projectile, and analyze how this in–out asymmetry depends of the angle of incidence.

  19. DYNAMIC RESPONSE OF A RIGID,PERFECTLY PLASTIC FREE-FREE BEAM STRUCK BY A PROJECTILE ATANY CROSS-SECTION ALONG ITS SPAN

    Institute of Scientific and Technical Information of China (English)

    YangJialing; LiuXuhong

    2004-01-01

    The rigid, perfectly plastic dynamic response of a free-free beam subjected to impact by a projectile at any cross-section is studied. The instantaneous deformations of the beam are given through an analysis of the complete solution for rigid plastic structures. The influence of some parameters such as the input energy and mass ratio on the plastic deformation, travelling plastic hinge position and energy partitioning of the beam are discussed.

  20. Preequilibrium emission and target-projectile-like correlations for /sup 20/Ne+/sup 60/Ni at E(/sup 20/Ne) = 740 MeV

    Energy Technology Data Exchange (ETDEWEB)

    D' Onofrio, A.; del Campo, J.G.; Delaunay, B.; Delaunay, J.; Dumont, H.; Andreozzi, F.; Brondi, A.; Moro, R.; Romano, M.; Terrasi, F.; and others

    1989-03-01

    Inclusive ..gamma.. rays at 90/sup 0/ and 125/sup 0/ and particle spectra (for Z = 1 to 6) at 14/sup 0/ and (Z = 1 to 4) at 120/sup 0/ and 150/sup 0/ were measured. Particle-..gamma..-ray coincidences were obtained. Cross sections for heavy residuals were extracted from in-beam ..gamma..-ray and radioactivity measurements. Target-projectile-like correlations were well reproduced using a geometrical abrasion model plus preequilibrium and equilibrium decay.

  1. Human body projectiles implantation in victims of suicide bombings and implications for health and emergency care providers: the 7/7 experience

    OpenAIRE

    Patel, HDL; Dryden, S; Gupta, A; Stewart, N.

    2012-01-01

    INTRODUCTION On 7 July 2005 four suicide bombings occurred on the London transport systems. In some of the injured survivors, bone fragments were embedded as biological foreign bodies. The aim of this study was to revisit those individuals who had sustained human projectile implantation injuries as a result of the bomb blasts at all scenes, review the process of body parts mapping and DNA identification at the scene, detail the management of such injuries and highlight the protocols that have...

  2. Flash X-ray cinematography analysis of dwell and penetration of small caliber projectiles with three types of SiC ceramics

    Directory of Open Access Journals (Sweden)

    Elmar Strassburger

    2016-06-01

    Full Text Available In order to improve the performance of ceramic composite armor it is essential to know the mechanisms during each phase of the projectile–target interaction and their influence on the penetration resistance. Since the view on the crater zone and the tip of a projectile penetrating a ceramic is rapidly getting obscured by damaged material, a flash X-ray technique has to be applied in order to visualize projectile penetration. For this purpose, usually several flash X-ray tubes are arranged around the target and the radiographs are recorded on film. At EMI a flash X-ray imaging method has been developed, which provides up to eight flash radiographs in one experiment. A multi-anode 450 kV flash X-ray tube is utilized with this method. The radiation transmitted through the target is then detected on a fluorescent screen. The fluorescent screen converts the radiograph into an image in the visible wavelength range, which is photographed by means of a high-speed camera. This technique has been applied to visualize and analyze the penetration of 7.62 mm AP projectiles into three different types of SiC ceramics. Two commercial SiC grades and MICASIC (Metal Infiltrated Carbon derived SiC, a C-SiSiC ceramic developed by DLR, have been studied. The influences, not only of the ceramic but also the backing material, on dwell time and projectile erosion have been studied. Penetration curves have been determined and their relevance to the ballistic resistance is discussed.

  3. Research on critical behaviour during fragmentation of the projectile in the Xe+Sn (at 50 MeV/A) reaction; Recherche d`un comportement critique dans la fragmentation du projectile dans la reaction Xe+Sn a 50 MeV/A

    Energy Technology Data Exchange (ETDEWEB)

    Benlliure, J.

    1995-03-01

    The study of moments of fragments charge distributions produced in heavy ions collisions can give us evidence of a critical behavior of nuclear matter which could explain the multifragmentation pattern. From an experimental point of view, in order to perform this capabilities of the INDRA detector has made it possible to identify all these particles and to reconstruct the initial projectile-like fragment coming from binary collisions in the reaction Xe+Sn at 50 MeV/A. We have selected events where the initial projectile-like fragments keep their entire charge in a large range of excitation energy. The study of these fragment`s characteristics show clearly a change in the deexcitation pattern. The evolution of moments of the fragment charge distributions has been reproduced within a percolation model, in this sense we can interpreter this change in the deexcitation pattern as a function of the initial projectile-like fragment`s size shows the existence of finite-size effects. However, the signature of a phase transition remains independent on the projectile-like fragment`s size. (author). 74 refs., 58 figs., 9 tabs.

  4. Study on Titanium Alloy TC4 Ballistic Penetration Resistance Part Ⅰ: Ballistic Impact Tests

    Institute of Scientific and Technical Information of China (English)

    ZHANG Tao; CHEN Wei; GUAN Yupu; GAO Deping

    2012-01-01

    Ballistic impact test of different-scale casings is an efficient way to demonstrate the casing containment capability at the preliminary design stage of the engine.For the sake of studying the titanium alloy TC4 casing performance,the ballistic tests of flat and curved simulation casing are implemented by using two flat blades of different sizes as the projectile.The impact mechanism and failure of the target are discussed.Impact of the projectile is a highly nonlinear transient process with the large deformation of the target.On the impact,failures of the flat casing and the subscale casing are similar,concluding two parts,the global dishing and localized ductile tearing.The main localized failure mode combines plugging (shear) and petaling (shear) if the projectile perforates or penetrates,while crater (shear) if the projectile rebounds.The ballistic limit equation is verified by the test data and the results show that this empirical equation could be a practical way to estimate the critical velocity.

  5. Excitation function for the production of 262Bh (Z = 107) in theodd-Z projectile reaction 208Pb(55Mn, n)

    Energy Technology Data Exchange (ETDEWEB)

    Folden III, C.M.; Nelson, S.L.; Dullmann, Ch.E.; Schwantes, J.M.; Sudowe, R.; Zielinski, P.M.; Gregorich, K.E.; Nitsche, H.; Hoffman, D.C.

    2005-05-16

    The excitation function for production of 262Bh in the odd-Z-projectile reaction 208Pb(55Mn,n) has been measured at three projectile energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, 33 decay chains originating from 262Bh and 2 decay chains originating from 261Bh were observed. The measured decay properties are in good agreement with previous reports. The maximum cross section of 540 +180 - 150 pb is observed at a lab-frame center-of-target energy of 264.0 MeV and is more than fives times larger than that expected based on previously reported results for production of 262Bh in the analogous even-Z-projectile reaction 209Bi(54Cr,n). Our results indicate that the optimum beam energy in one-neutron-out heavy-ion fusion reactions can be estimated simply using the ''Optimum Energy Rule'' proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski.

  6. Excitation function for the production of 262Bh (Z=107) in the odd-Z-projectile reaction 208Pb(55Mn, n)

    International Nuclear Information System (INIS)

    The excitation function for production of 262Bh in the odd-Z-projectile reaction 208Pb(55Mn, n) has been measured at three projectile energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, 33 decay chains originating from 262Bh and 2 decay chains originating from 261Bh were observed. The measured decay properties are in good agreement with previous reports. The maximum cross section of 540-150+180 pb is observed at a lab-frame center-of-target energy of 264.0 MeV and is more than five times larger than that expected based on previously reported results for production of 262Bh in the analogous even-Z-projectile reaction 209Bi(54Cr, n). Our results indicate that the optimum beam energy in one-neutron-out heavy-ion fusion reactions can be estimated simply using the optimum energy rule proposed by SwiaPtecki, Siwek-Wilczynska, and Wilczynski

  7. Projectile points as signs of violence in collective burials during the 4th and the 3rd millenium Cal. BC in the N.E. of the Iberian Peninsula.

    OpenAIRE

    Márquez, Belén; Gibaja, Juan Francisco; González Urquijo, Jesús E.; Ibáñez, Juan José; Palomo, Antoni

    2009-01-01

    During the Late Neolithic and the Chalcolithic in the NE of the Iberian Peninsula two main changes in the burials take place with respect to the previous period: the appearance of collective burials and the high proportion of projectile points among the tools recovered inside the monuments. What is the meaning of these projectile points? Without ruling out the possibility that some of these points were intentionally deposited, stressing the symbolic relevance of these hunting/war tools, we th...

  8. Study of uranium dioxyde sputtering induced by multicharged heavy ions at low and very low kinetic energy: projectile charge effect; Etude de la pulverisation du dioxyde d'uranium induite par des ions lourds multicharges de basse et tres basse energie cinetique; effet de la charge du projectile

    Energy Technology Data Exchange (ETDEWEB)

    Haranger, F

    2003-12-01

    Ion beam irradiation of a solid can lead to the emission of neutral or ionized atoms, molecules or clusters from the surface. This comes as a result of the atomic motion in the vicinity of the surface, induced by the transfer of the projectile energy. Then, the study of the sputtering process appears as a means to get a better understanding of the excited matter state around the projectile trajectory. In the case of slow multicharged ions, a strong electronic excitation can be achieved by the projectile neutralization above the solid surface and / or its deexcitation below the surface. Parallel to this, the slowing down of such ions is essentially related to elastic collision with the target atoms. The study of the effect of the initial charge state of slow multicharged ions, in the sputtering process, has been carried out by measuring the absolute angular distributions of emission of uranium atoms from a uranium dioxide surface. The experiments have been performed in two steps. First, the emitted particles are collected onto a substrate during irradiation. Secondly, the surface of the collectors is analyzed by Rutherford Backscattering Spectrometry (RBS). This method allows the characterization of the emission of neutrals, which are the vast majority of the sputtered particles. The results obtained provide an access to the evolution of the sputtering process as a function of xenon projectile ions charge state. The measurements have been performed over a wide kinetic energy range, from 81 down to 1.5 keV. This allowed a clear separation of the contribution of the kinetic energy and initial projectile charge state to the sputtering phenomenon. (author)

  9. Ballistic Performance of Alumina and Zirconia-toughened Alumina Against 7.62 Armour Piercing Projectile

    Directory of Open Access Journals (Sweden)

    S G. Savio

    2014-09-01

    Full Text Available A study was carried out to compare the ballistic performance of high purity alumina and zirconia-toughened alumina (ZTA using depth of penetration (DoP test configuration against 7.62 mm armour piercing (AP ammunition. The effect of tile thickness on the differential efficiency factor (DEF was studied for tile thickness in the range of 3 mm to 6 mm for alumina tiles and 3 mm to 5 mm for ZTA tiles. The DEF is found to increase as tile thickness increases. An analysis on the failed shots showed that the residual shot weight does not follow a single linear relationship with ceramic tile thickness unlike the residual DoP for all thicknesses of tiles. Post-ballistic analysis on ceramic powder for particle size distribution was carried out and the results are presented.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.477-483, DOI:http://dx.doi.org/10.14429/dsj.64.6745

  10. Monitoring the irradiation field of 12C and 16O SOBP beams using positron emitters produced through projectile fragmentation reactions

    International Nuclear Information System (INIS)

    In order to effectively utilize the prominent properties of heavy ions in radiotherapy, it is important to evaluate both the position of the field irradiated with incident ions and the absorbed dose distribution in a patient's body. One of the methods for this purpose is the utilization of the positron emitters produced through the projectile fragmentation reactions of stable heavy ions with target nuclei. In heavy-ion therapy, spread-out Bragg peak (SOBP) beams are used to achieve uniform biological dose distributions in the whole tumor volume. Therefore, in this study, we designed SOBP beams of 30 and 50 mm water-equivalent length (mmWEL) in width for 12C and 16O, and carried out irradiation experiments using them. Water, polyethylene and polymethyl methacrylate were selected as targets to simulate a human body. Pairs of annihilation gamma rays were detected by means of a limited-angle positron camera for 500 s, and annihilation gamma-ray distributions were obtained. The maximum likelihood estimation (MLE) method was applied to the detected distributions for evaluating the positions of the distal and proximal edges of the SOBP in a target. The differences between the positions evaluated with the MLE method and those derived from the measured dose distributions were less than 1.7 mm and 2.5 mm for the distal and the proximal edge, respectively, in all irradiation conditions. When the positions of both edges are determined with the MLE method, the most probable shape of the dose distribution in a target can be estimated simultaneously. The close agreement between the estimated and the measured distributions implied that the shape of the dose distribution in an irradiated target could be evaluated from the detected annihilation gamma-ray distribution

  11. Ballistic penetration test results for Ductal and ultra-high performance concrete samples.

    Energy Technology Data Exchange (ETDEWEB)

    Reinhart, William Dodd; Thornhill, Tom Finley, III (KTech)

    2010-03-01

    This document provides detailed test results of ballistic impact experiments performed on several types of high performance concrete. These tests were performed at the Sandia National Laboratories Shock Thermodynamic Applied Research Facility using a 50 caliber powder gun to study penetration resistance of concrete samples. This document provides test results for ballistic impact experiments performed on two types of concrete samples, (1) Ductal{reg_sign} concrete is a fiber reinforced high performance concrete patented by Lafarge Group and (2) ultra-high performance concrete (UHPC) produced in-house by DoD. These tests were performed as part of a research demonstration project overseen by USACE and ERDC, at the Sandia National Laboratories Shock Thermodynamic Applied Research (STAR) facility. Ballistic penetration tests were performed on a single stage research powder gun of 50 caliber bore using a full metal jacket M33 ball projectile with a nominal velocity of 914 m/s (3000 ft/s). Testing was observed by Beverly DiPaolo from ERDC-GSL. In all, 31 tests were performed to achieve the test objectives which were: (1) recovery of concrete test specimens for post mortem analysis and characterization at outside labs, (2) measurement of projectile impact velocity and post-penetration residual velocity from electronic and radiographic techniques and, (3) high-speed photography of the projectile prior to impact, impact and exit of the rear surface of the concrete construct, and (4) summarize the results.

  12. Testing double ionization mechanisms with highly-charged ions

    International Nuclear Information System (INIS)

    Double ionization of He target atoms by intermediate- to high-velocity charged ions is considered in terms of two mechanisms: (1) a two-step (TS) process in which both target electrons are removed in separate direct interactions with the projectile, and (2) a one-step mechanism in which one electron is liberated in a single projectile-target interaction followed by subsequent ''shakeoff'' (SO) of the second electron. Measured double-to-single ionization ratios are used to exhibit and test the underlying mechanisms of double ionization. It is found that these ratios exhibit a high degree of universality as a function of v/q, where v is the velocity of the ion and q is its charge. The results strongly suggest that the important factor in determining the regions of validity for TS and SO is the ionic charge divided by the impact velocity and not just the impact velocity itself

  13. One testing method of dynamic linearity of an accelerometer

    Directory of Open Access Journals (Sweden)

    Lei Jing-Yu

    2015-01-01

    Full Text Available To effectively test dynamic linearity of an accelerometer over a wide rang of 104 g to about 20 × 104g, one published patent technology is first experimentally verified and analysed, and its deficient is presented, then based on stress wave propagation theory on the thin long bar, the relation between the strain signal and the corresponding acceleration signal is obtained, one special link of two coaxial projectile is developed. These two coaxial metal cylinders (inner cylinder and circular tube are used as projectiles, to prevent their mutual slip inside the gun barrel during movement, the one end of two projectiles is always fastened by small screws. Ti6-AL4-V bar with diameter of 30 mm is used to propagate loading stress pulse. The resultant compression wave can be measured by the strain gauges on the bar, and a half –sine strain pulse is obtained. The measuring accelerometer is attached on the other end of the bar by a vacuum clamp. In this clamp, the accelerometer only bear compression wave, the reflected tension pulse make the accelerometer off the bar. Using this system, dynamic linearity measurement of accelerometer can be easily tested in wider range of acceleration values. And a really measuring results are presented.

  14. One testing method of dynamic linearity of an accelerometer

    Science.gov (United States)

    Lei, Jing-Yu; Guo, Wei-Guo; Tan, Xue-Ming; Shi, Yun-Bo

    2015-09-01

    To effectively test dynamic linearity of an accelerometer over a wide rang of 104 g to about 20 × 104g, one published patent technology is first experimentally verified and analysed, and its deficient is presented, then based on stress wave propagation theory on the thin long bar, the relation between the strain signal and the corresponding acceleration signal is obtained, one special link of two coaxial projectile is developed. These two coaxial metal cylinders (inner cylinder and circular tube) are used as projectiles, to prevent their mutual slip inside the gun barrel during movement, the one end of two projectiles is always fastened by small screws. Ti6-AL4-V bar with diameter of 30 mm is used to propagate loading stress pulse. The resultant compression wave can be measured by the strain gauges on the bar, and a half -sine strain pulse is obtained. The measuring accelerometer is attached on the other end of the bar by a vacuum clamp. In this clamp, the accelerometer only bear compression wave, the reflected tension pulse make the accelerometer off the bar. Using this system, dynamic linearity measurement of accelerometer can be easily tested in wider range of acceleration values. And a really measuring results are presented.

  15. Measurement of {sup 63}Ni and {sup 59}Ni by accelerator mass spectrometry using characteristic projectile x-rays

    Energy Technology Data Exchange (ETDEWEB)

    McAninch, J.E.; Hainsworth, L.J.; Marchetti, A.A. [and others

    1996-05-01

    The long-lived isotopes of nickel ({sup 59}Ni, {sup 63}Ni) have current and potential use in a number of applications including cosmic radiation studies, biomedical tracing, characterization of low-level radioactive wastes, and neutron dosimetry. Methods are being developed at LLNL for the routine detection of these isotopes by AMS. One intended application is in Hiroshima dosimetry. The reaction {sup 63}Cu(n,p){sup 63}Ni has been identified as one of a small number of reactions which might be used for the direct determination of the fast neutron fluence emitted by the Hiroshima bomb. AMS measurement of {sup 63}Ni(t{sub 1/2} = 100 y) requires the chemical removal of {sup 63}Cu, which is a stable isobar of {sup 63}Ni. Following the electrochemical separation of Ni from gram-sized copper samples, the Cu concentration is further lowered to < 2 x 10{sup -8} (Cu/Ni) using the reaction of Ni with carbon monoxide to form the gas Ni(CO){sub 4}. The Ni(CO){sub 4} is thermally decomposed directly in sample holders for measurement by AMS. After analysis in the AMS spectrometer, the ions are identified using characteristic projectile x-rays, allowing further rejection of remaining {sup 63}Cu. In a demonstration experiment, {sup 63}Ni was measured in Cu wires (2-20 g) which had been exposed to neutrons from a {sup 252}Cf source. We successfully measured {sup 63}Ni at levels necessary for the measurement of Cu samples exposed near the Hiroshima hypocenter. For the demonstration samples, the Cu content was chemically reduced by a factor of 10{sup 12} with quantitative retention of {sup 63}Ni. Detection sensitivity (3{sigma}) was {approximately}20 fg {sup 63}Ni in 1 mg Ni carrier ({sup 63}Ni/Ni {approx} 2 x 10{sup -11}). Significant improvements in sensitivity are expected with planned incremental changes in the methods. Preliminary results indicate that a similar sensitivity is achievable for {sup 59}Ni (t{sub 1/2} = 10{sup 5} y).

  16. Measurement of K X-ray intensity ratios in Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn employing carbon and nitrogen projectiles - VTT method

    International Nuclear Information System (INIS)

    A method is suggested to effect the self absorption correction in a different way to estimate the K X-ray intensity ratios particularly when heavy ions are used as projectiles. Employing this method, the Kβ/Kα intensity ratios are measured in some 3d shell elements by using Carbon and Nitrogen ions as exciting agents. The Kβ/Kα intensity ratios thus obtained in the present work are compared with the intensity ratios due to some previous authors and also with Scofield theoretical values. (orig.)

  17. Relativistic electron- and proton-impact ionization of highly stripped heavy ions determined from projectile-electron loss in H2 and He

    International Nuclear Information System (INIS)

    We show that electron- and proton-impact ionization cross sections for highly stripped heavy ions can be deduced from the projectile-electron-loss cross sections determined by collisions with a H2 and a He target. We measure electron loss for 100- and 380-MeV/u Au52+, and 405-MeV/u U86+ in H2 and He targets, and extract the electron- and proton-impact ionization cross sections. Our results are compared with calculations and with channeling experiments

  18. Fission of spin-aligned projectile-like nuclei in the interactions of 29 MeV/nucleon 208Pb with 197Au

    International Nuclear Information System (INIS)

    Binary fission of projectile-like nuclei was investigated in the interaction of 29 MeV/nucleon Pb on Au, together with the associated neutron multiplicity. Fission is only observed in rather peripheral collisions and represents approximately 20% of the total reaction cross-section. The fission process occurs after collisions in which up to 550 MeV have been dissipated. The angular and energy distribution of the fragments can be accounted for by assuming a noticeable spin alignment of the fissioning nuclei. (author) 18 refs.; 3 figs

  19. Direct mass measurements of neutron-rich $^{86}$Kr projectile fragments and the persistence of neutron magic number $N$ = 32 in Sc isotopes

    OpenAIRE

    Xu, Xing; Wang, Meng; Zhang, Yu-Hu; Xu, Hu-Shan; Shuai, Peng; Tu, Xiao-Lin; Litvinov, Yuri A.; Zhou, Xiao-Hong; Sun, Bao-hua; Yuan, You-Jin; Xia, Jia-wen; Yang, Jian-Cheng; Blaum, Klaus; Chen, Rui-jiu; Chen, Xiang-cheng

    2016-01-01

    In this paper, we present direct mass measurements of neutron-rich $^{86}$Kr projectile fragments conducted at the HIRFL-CSR facility in Lanzhou by employing the Isochronous Mass Spectrometry (IMS) method. The new mass excesses of $^{52-54}$Sc nuclides are determined to be -40492(82), -38928(114), -34654(540) keV, which show a significant increase of binding energy compared to the reported ones in the Atomic Mass Evaluation 2012 (AME12). In particular, $^{53}$Sc and $^{54}$Sc are more bound b...

  20. Penetrating injury to the chest by an attenuated energy projectile: a case report and literature review of thoracic injuries caused by "less-lethal" munitions

    Directory of Open Access Journals (Sweden)

    Porto Leonardo BO

    2009-06-01

    Full Text Available Abstract We present the case of a patient who sustained a penetrating injury to the chest caused by an attenuated energy rubber bullet and review the literature on thoracic injuries caused by plastic and rubber "less-lethal" munitions. The patient of this report underwent a right thoracotomy to extract the projectile as well as a wedge resection of the injured lung parenchyma. This case demonstrates that even supposedly safe riot control munition fired at close range, at the torso, can provoke serious injury. Therefore a thorough investigation and close clinical supervision are justified.

  1. Impact Testing and Analysis of Composites for Aircraft Engine Fan Cases

    Science.gov (United States)

    Roberts, Gary D.; Revilock, Duane M.; Binienda, Wieslaw K.; Nie, Walter Z.; Mackenzie, S. Ben; Todd, Kevin B.

    2002-01-01

    The fan case in a jet engine is a heavy structure because of its size and because of the requirement that it contain a blade released during engine operation. Composite materials offer the potential for reducing the weight of the case. Efficient design, test, and analysis methods are needed to efficiently evaluate the large number of potential composite materials and design concepts. The type of damage expected in a composite case under blade-out conditions was evaluated using a subscale test in which a glass/epoxy composite half-ring target was impacted with a wedge-shaped titanium projectile. Fiber shearing occurred near points of contact between the projectile and target. Delamination and tearing occurred on a larger scale. These damage modes were reproduced in a simpler test in which flat glass/epoxy composites were impacted with a blunt cylindrical projectile. A surface layer of ceramic eliminated fiber shear fracture but did not reduce delamination. Tests on 3D woven carbon/epoxy composites indicated that transverse reinforcement is effective in reducing delamination. A 91 cm (36 in.) diameter full-ring sub-component was proposed for larger scale testing of these and other composite concepts. Explicit, transient, finite element analyses indicated that a full-ring test is needed to simulate complete impact dynamics, but simpler tests using smaller ring sections are adequate when evaluation of initial impact damage is the primary concern.

  2. FAA Development of Reliable Modeling Methodologies for Fan Blade Out Containment Analysis. Part 2; Ballistic Impact Testing

    Science.gov (United States)

    Revilock, Duane M.; Pereira, J. Michael

    2008-01-01

    This report summarizes the ballistic impact testing that was conducted to provide validation data for the development of numerical models of blade out events in fabric containment systems. The ballistic impact response of two different fiber materials - Kevlar 49 (E.I. DuPont Nemours and Company) and Zylon AS (Toyobo Co., Ltd.) was studied by firing metal projectiles into dry woven fabric specimens using a gas gun. The shape, mass, orientation and velocity of the projectile were varied and recorded. In most cases the tests were designed such that the projectile would perforate the specimen, allowing measurement of the energy absorbed by the fabric. The results for both Zylon and Kevlar presented here represent a useful set of data for the purposes of establishing and validating numerical models for predicting the response of fabrics under conditions simulating those of a jet engine blade release situations. In addition some useful empirical observations were made regarding the effects of projectile orientation and the relative performance of the different materials.

  3. Nano-biolistics: a method of biolistic transfection of cells and tissues using a gene gun with novel nanometer-sized projectiles

    Directory of Open Access Journals (Sweden)

    Lummis Sarah CR

    2011-06-01

    Full Text Available Abstract Background Biolistic transfection is proving an increasingly popular method of incorporating DNA or RNA into cells that are difficult to transfect using traditional methods. The technique routinely uses 'microparticles', which are ~1 μm diameter projectiles, fired into tissues using pressurised gas. These microparticles are efficient at delivering DNA into cells, but cannot efficiently transfect small cells and may cause significant tissue damage, thus limiting their potential usefulness. Here we describe the use of 40 nm diameter projectiles - nanoparticles - in biolistic transfections to determine if they are a suitable alternative to microparticles. Results Examination of transfection efficiencies in HEK293 cells, using a range of conditions including different DNA concentrations and different preparation procedures, reveals similar behaviour of microparticles and nanoparticles. The use of nanoparticles, however, resulted in ~30% fewer damaged HEK293 cells following transfection. Biolistic transfection of mouse ear tissue revealed similar depth penetration for the two types of particles, and also showed that 20% in microparticle-transfected samples. Visualising details of small cellular structures was also considerably enhanced when using nanoparticles. Conclusions We conclude that nanoparticles are as efficient for biolistic transfection as microparticles, and are more appropriate for use in small cells, when examining cellular structures and/or where tissue damage is a problem.

  4. Decay analysis of pre-actinide and trans-actinide nuclei formed using various projectiles on a 197Au target at ECN*=60 MeV

    Science.gov (United States)

    Grover, Neha; Kaur, Gurvinder; Sharma, Manoj K.

    2016-01-01

    The collective clusterization approach of the dynamical cluster decay model (DCM) has been applied to study the decay of odd mass nuclei 223Pa*, 215Fr*, 227Np*, and 233Am*, which are formed in heavy-ion-induced reactions. The aim of this study is to investigate the decay pattern and related behavior of these heavy mass nuclei formed in four distinct reactions involving different projectiles (with mass A =18 -36 ) induced on 197Au target nucleus. Further, in order to analyze the role of deformations, the calculations have been done by considering spherical choice of fragmentation as well as with inclusion of quadrupole (β2) deformation. For the heavy mass region, with fission being the dominant decay mode, an attempt has been made to investigate the effect of projectile mass in reference to fission decay patterns of the pre-actinide 215Fr* nucleus and the trans-actinide nuclei 227Np* 223Pa*, 223Am* and formed at common excitation energy, ECN*=60 MeV . Besides this, the shell closure effects and the role of orientation have been explored, which suggest the presence of a noncompound nucleus process such as quasifission (QF) for the odd mass nuclei under consideration. For both the compound nucleus and the noncompound nucleus processes, the results obtained using DCM are found to have nice agreement with experimental observations. The isotopic and isobaric analysis is also worked out so as to have a comprehensive idea about the dynamics involved.

  5. Muerte por proyectil de arma de fuego con orificio de entrada natural Death caused by a projectile gun with a natural entrance hole

    Directory of Open Access Journals (Sweden)

    F. Sánchez

    2010-09-01

    Full Text Available Un proyectil de arma de fuego puede penetrar en el organismo por cualquier parte, originando una lesión cuya morfología puede ser muy variada en función de múltiples factores. No obstante, en ocasiones el lugar de entrada del proyectil puede coincidir con un orificio natural del cuerpo, por lo que la lesión externa no existe. Presentamos un caso de muerte por un único proyectil de arma de fuego cuyo lugar de penetración es uno de los orificios nasales, con la particularidad de que la bala quedó alojada en el interior del cuerpo, no existiendo por tanto lesión de salida. En estas circunstancias se hacen indispensables las técnicas radiológicas como paso previo a la autopsia.A firearm projectile can penetrate through any place of the body, causing injuries whose morphology can be different depending on several factors. However, sometimes the shotgun entrance hole coincides with a body orifice, so the entrance wound could not exist. The authors present a case of a death caused by a single firearm projectile which penetrated through one of the nostrils. The bullet was lodged inside of the body without an exit wound. In those circumstances the radiological techniques are indispensable before to perform the autopsy.

  6. Systematic experimental survey on projectile fragmentation and fission induced in collisions of 238U at 1 A GeV with lead

    International Nuclear Information System (INIS)

    Projectile fragmentation and fission, induced in collisions of 238U at 1 A GeV with lead, have systematically been studied. A complete survey on the isotopic production cross sections of all elements between vanadium (Z = 23) and rhenium (Z = 75) down to a cross section of 0.1 mb is given. About 600 isotopes produced in fragmentation and about 600 isotopes produced in fission were identified in the GSI fragment separator FRS from magnetic rigidities, time-of-flight values, and the energy loss in an ionisation chamber. In addition, the velocity distributions of all these reaction products have been mapped, and the products are unambiguously attributed to the different reaction mechanisms due to their kinematical properties. The results are compared with empirical systematics and previous data. The velocity of the fragments obtained in the fission process by the Coulomb repulsion allows to reconstruct the TKE-value of the break-up and to identify the atomic number of the fissioning nucleus in hot fission. The mean velocities of light projectile fragments were found to be higher than the beam velocity. (orig.)

  7. Decay analysis of compound nuclei with mass A$\\sim 30-200$ formed in the reactions involving loosely bound projectiles

    CERN Document Server

    Kaur, Mandeep; Sharma, Manoj K; Gupta, Raj K

    2015-01-01

    The dynamics of the reactions forming compound nuclei using loosely bound projectiles is analysed within the framework of dynamical cluster decay model (DCM) of Gupta and Collaborators. We have analysed different reactions with $^{7}Li$, $^{9}Be$ and $^{7}Be$ as neutron rich and neutron deficient projectiles, respectively, on different targets at the three $E_{lab}$ values, forming compound nuclei within the mass region A$\\sim 30-200$. The contributions of light particles LPs ($A\\le4$) cross sections $\\sigma_{LP}$, energetically favoured intermediate mass fragments IMFs ($5 \\le A_2 \\le 20$) cross sections $\\sigma_{IMF}$ as well as fusion-fission $\\it{ff}$ cross sections $\\sigma_{ff}$ constitute the $\\sigma_{fus}$ (=$\\sigma_{LP}$+$\\sigma_{IMF}$+$\\sigma_{ff}$) for these reactions. The contribution of the emitted LPs, IMFs and ff fragments is added for all the angular momentum upto the $\\ell_{max}$ value, for the resepctive reactions. Interestingly, we find that the $\\Delta R^{emp}$, the only parameter of model ...

  8. Systematic experimental survey on projectile fragmentation and fission induced in collisions of {sup 238}U at 1 A GeV with lead

    Energy Technology Data Exchange (ETDEWEB)

    Enquist, T.; Benlliure, J.; Farget, F.; Schmidt, K.H.; Armbruster, P. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Bernas, M.; Tassan-Got, L. [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire; Boudard, A.; Legrain, R.; Volant, C. [CEA Centre d`Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de Physique des Particules, de Physique Nucleaire et de l`Instrumentation Associee (DAPNIA); Boeckstiegel, C.; Jong, M. de [Technische Univ. Darmstadt (Germany); Dufour, J.P. [CEA Centre d`Etudes Nucleaires de Bordeaux-Gradignan, 33 - Gradignan (France)

    1999-03-01

    Projectile fragmentation and fission, induced in collisions of {sup 238}U at 1 A GeV with lead, have systematically been studied. A complete survey on the isotopic production cross sections of all elements between vanadium (Z = 23) and rhenium (Z = 75) down to a cross section of 0.1 mb is given. About 600 isotopes produced in fragmentation and about 600 isotopes produced in fission were identified in the GSI fragment separator FRS from magnetic rigidities, time-of-flight values, and the energy loss in an ionisation chamber. In addition, the velocity distributions of all these reaction products have been mapped, and the products are unambiguously attributed to the different reaction mechanisms due to their kinematical properties. The results are compared with empirical systematics and previous data. The velocity of the fragments obtained in the fission process by the Coulomb repulsion allows to reconstruct the TKE-value of the break-up and to identify the atomic number of the fissioning nucleus in hot fission. The mean velocities of light projectile fragments were found to be higher than the beam velocity. (orig.) 41 refs.

  9. SSNTD studies of lead nuclei fission induced by relativistic p, d, He and sup 1 sup 2 C projectiles inside massive Pb and U targets

    CERN Document Server

    Perelygin, V P; Krivopustov, M I; Petrova, R I; Abdullaev, I G; Bradnova, V; Knjazeva, G P; Brandt, R; Ochs, M; Wan, J S; Vater, P

    1999-01-01

    A series of experiments was carried out with relativistic protons, deuterons, helium and carbon-12 projectiles accelerated at SYNCHOPHASOTRON LHE, Dubna which hit massive Pb and U targets. The beam profiles and intensities of both primary particles and secondary fast neutrons were measured using plastic SSNTD inside the massive cylinder blocks of Cu, Pb and U by counting of fission fragment tracks due to the induced fission of Pb nuclei. The beam diameter increases typically by 20-30% at the depth 10 and 20 cm. With increasing the energy of projectiles the number of secondary neutrons rises with the depth for protons, deuterons and helium ions. Nevertheless, for sup 1 sup 2 C ions beams with changing the energy from 18 GeV to 44 GeV we first observe the effect of significant increase both the yield of secondary fast neutrons and the half-width of the beam. The observed enhanced yield of secondary fast neutrons confirms unusual behavior of nuclear interaction cross section of 44 GeV sup 1 sup 2 C ions observed...

  10. Hard-driven rail-gun tests

    International Nuclear Information System (INIS)

    A number of prototype rail-gun designs have been tested, powered by explosive magnetic flux compression generators. Peak currents as high as 1.3 MA were delivered. Rail guns with 50-mm-thick Kevlar fiberwound structural shells were able to survive these high currents with minimum mechanical damage and were refired after enlarging the bores 0.2 to 0.4 mm to remove arc damage. In some tests, mechanical damage occurred that was apparently caused by the rebound of the gun after firing. Although the Kevlar shells had more than adequate strength, they appeared to lack sufficient stiffness, allowing excessive deflections. The use of a steel structural shell with a Kevlar sleeve was an improvement. Intrusion into the seams of the rail guns and condensation of material from the plasma armature were observed. Improved sealing of seams is indicated. In some cases, we suspect maldistribution of current within the gun; that is, not all the current delivered to the breech of the gun seemed to reach the plasma armature. Experiments are being designed to quantify the effects discussed. Rail guns of advanced design are being fabricated. An 18-g titanium projectile was accelerated to 2.4 km/s in a 16-mm-round-bore, 0.6-m-long gun, 4-6 g polycarbonate projectiles were accelerated to 3.5 km/s in 13-mm-square-bore, 1.2-m-long rail guns. All tests were conducted at atmospheric pressure

  11. A new dynamic test for the identification of high speed friction law using a gas-gun device

    Science.gov (United States)

    Nistor, I.; Pantalé, O.; Caperaa, S.; Sattouf, C.

    2003-09-01

    In the framework of metal forming, which involves high speed loads, the determination of the friction law is one of the most essential topics. Especially for Finite-element simulation the development of innovative local friction laws improves the quality of the numerical results. One of the most critical point reside in the accuracy of the identification of the governing friction law parameters. A new experimental test is based on conical extrusion. The idea is to launch a cylindrical projectile into a target provided with a conical bore prolonged with a cylindrical one. The projectile is stopped by friction forces occurring at the interface between those materials. After impact the length of extrusion is taken into account for friction law identification. The experimental set-up used is a ballistic gas-gun device capable to launch the projectile, in vacuum conditions, up to 300m/s. The experiment is simulated by a numerical model using ABAQUS Explicit finite-element code. This code allows the implementation of various user friction laws through a FORTRAN subroutine. In order to obtain accurate results, the viscoplastic constitutive law used for both materials (projectile and target) was previously experimentally identified. The friction law identification uses a combined Monte-Carlo and Levenberg-Marquardt algorithm which provides a very precisely set of parameters law. The test presented in this paper involves two metallic materials: steel 42CrMo4 for the target and aluminum 2017 for the projectile. The friction law for the pair of materials used was validated using experimental test at different speeds of impact (149 up to 235m/s) and the results are quite good proving a good identification of the friction law parameters.

  12. Questions for Parents to Ask about School Adaptations. PHP-c91

    Science.gov (United States)

    PACER Center, 2004

    2004-01-01

    A child with a disability who has an Individualized Education Program (IEP) or Section 504 Accommodation Plan may need extra help and support to participate in school. It takes thoughtful planning to choose adaptations, based on a child's disability, to help the child learn or have access to learning. Appropriate accommodations vary with…

  13. A novel facility for reduced-gravity testing: A setup for studying low-velocity collisions into granular surfaces.

    Science.gov (United States)

    Sunday, C; Murdoch, N; Cherrier, O; Morales Serrano, S; Valeria Nardi, C; Janin, T; Avila Martinez, I; Gourinat, Y; Mimoun, D

    2016-08-01

    This work presents an experimental design for studying low-velocity collisions into granular surfaces in low-gravity. In the experiment apparatus, reduced-gravity is simulated by releasing a free-falling projectile into a surface container with a downward acceleration less than that of Earth's gravity. The acceleration of the surface is controlled through the use of an Atwood machine, or a system of pulleys and counterweights. The starting height of the surface container and the initial separation distance between the projectile and surface are variable and chosen to accommodate collision velocities up to 20 cm/s and effective accelerations of ∼0.1 to 1.0 m/s(2). Accelerometers, placed on the surface container and inside the projectile, provide acceleration data, while high-speed cameras capture the collision and act as secondary data sources. The experiment is built into an existing 5.5 m drop tower frame and requires the custom design of all components, including the projectile, surface sample container, release mechanism, and deceleration system. Data from calibration tests verify the efficiency of the experiment's deceleration system and provide a quantitative understanding of the performance of the Atwood system. PMID:27587140

  14. Study on measurement method of the projectiles velocity and target coordinates of twin-tube volleyed weapons%双管齐射武器弹丸速度和着靶坐标测试方法研究

    Institute of Scientific and Technical Information of China (English)

    邹剑军; 王文博; 宋玉贵; 王国珲

    2011-01-01

    为了解决靶场测试中对于双管齐射武器飞行矢量和着靶坐标的测量问题,提高测试精度,介绍了一种基于多幕面装置的非接触测试方法.文中详细介绍了装置的构成,分析了测试方法的原理,并利用MatLab软件进行了仿真测试,根据其技术特点和仿真结果,对工程应用存在的实际问题进行了讨论.装置系统可以完成对双管齐射武器的测试,能够区分弹丸穿过幕面的正确时序并根据相应规则进行计算并得出结果.%A multi-screen structure of non-contacted method was presented to solve the measurement of the projectiles velocity and position of twin-tube volleyed weapons and to enhance the precision. The principle of the method and the device composition are explained in detail, and according to the MatLab to carry out simulation testing, discussing the practical problem based on engineering application. The device can differentiate the true moment of the twin-tube volleyed weapons when they are crossing the sky screen and the result will be obtained in terms of corresponding rules.

  15. Projectile charge state dependence of M-shell ionization of Au, Pb, Bi, and U by 1.42-MeV/amu fluorine ions

    International Nuclear Information System (INIS)

    The present study was undertaken to determine the direct ionization and electron capture contributions to vacancy production in the M-shells of 79Au, 82Pb, 83Bi and 92U for incident 199F ions. M-shell x-ray production cross sections have been measured for 1.42-MeV/amu 199Fq+ ions for q = 4,5,6,8,9. Enhancements in the target x-ray production cross sections were observed for projectiles with one and two K-shell vacancies over those without K-shell vacancies. Direct ionization and electron capture contributions to the vacancy production were extracted from the data and compared to the plane wave Born approximation and to the Oppenheimer-Brinkman-Kramers calculations of Nikolaev, respectively

  16. Sputtering of tungsten: an atomic view of a near-surface depleted zone created by a single 30 keV 63Cu+ projectile. Report No. 4118

    International Nuclear Information System (INIS)

    The vacancy structure of a near-surface depleted zone (DZ), created by a single 30 keV 63Cu+ ion in a tungsten field-ion microscope (FIM) specimen, was determined with atomic resolution. Both the irradiation and pulse field-evaporation experiments were performed in situ at less than or equal to 11 K, so that the observed vacancy structure was unaltered by the long-range migration of self-interstitial atoms. The following basic physical quantities were measured: (1) the number of vacancies; (2) the dimensions; (3) the vacancy concentration; (4) the distribution of first-nearest-neighbor vacancy clusters; and (5) the radial-distribution function for the vacancies out to ninth-nearest neighbor. The values of these quantities were shown to be similar for both the near-surface DZ and DZs created in the bulk of the same specimen by 30 keV 63Cu+ projectiles

  17. Filtre à fenêtre glissante pour l'estimation de l'attitude et des vitesses d'un projectile

    OpenAIRE

    Grandvallet, Bertrand; Zemouche, Ali; Boutayeb, Mohamed; Changey, Sébastien

    2010-01-01

    National audience Ce papier traite du problème de guidage d'un projectile stabilisé par rotation. Nous apportons une contribution au niveau la navigation grâce à des capteurs ”bas-coût” de type accéléromètres et magnétomètres. Les fortes non-linéarités présentes dans les équations d'états (dynamique et sortie) du modèle nous restreignent à l'utilisation de peu de méthodes d'estimation. Nous proposons ici un Filtre de Kalman Etendu (FKE) utilisant une fenêtre glissante sur les mesures pour ...

  18. Generation of ultra-high-pressure shocks by collision of a fast plasma projectile driven in the laser-induced cavity pressure acceleration scheme with a solid target

    Energy Technology Data Exchange (ETDEWEB)

    Badziak, J.; Rosiński, M. [Institute of Plasma Physics and Laser Microfusion, 01-497 Warsaw (Poland); Krousky, E. [Institute of Physics AS CR, 182 21 Prague 8 (Czech Republic); Kucharik, M.; Liska, R. [Czech Technical University, FNSPE, 160 41 Prague 6 (Czech Republic); Ullschmied, J. [Institute of Plasma Physics AS CR, 182 20 Prague 8 (Czech Republic)

    2015-03-15

    A novel, efficient method of generating ultra-high-pressure shocks is proposed and investigated. In this method, the shock is generated by collision of a fast plasma projectile (a macro-particle) driven by laser-induced cavity pressure acceleration (LICPA) with a solid target placed at the LICPA accelerator channel exit. Using the measurements performed at the kilojoule PALS laser facility and two-dimensional hydrodynamic simulations, it is shown that the shock pressure ∼ Gbar can be produced with this method at the laser driver energy of only a few hundred joules, by an order of magnitude lower than the energy needed for production of such pressure with other laser-based methods known so far.

  19. Theoretical study of projectile fragmentation in the reactions $^{112}$Sn + $^{112}$Sn and $^{124}$Sn + $^{124}$Sn at 1 GeV/nucleon

    CERN Document Server

    Imal, H; Buyukcizmeci, N; Ogul, R; Botvina, A S; Trautmann, W

    2014-01-01

    We analyze the production cross sections and isotopic distributions of projectile-like residues in the reactions $^{112}$Sn + $^{112}$Sn and $^{124}$Sn + $^{124}$Sn at an incident beam energy of 1 GeV/nucleon measured with the FRS fragment separator at the GSI laboratory. Calculations within the statistical multifragmentation model (SMM) for an ensemble of excited sources were performed with ensemble parameters determined previously for similar reactions at 600 MeV/nucleon. The obtained good agreement with the experiment establishes the universal properties of the excited spectator systems produced during the dynamical stage of the reaction. It is furthermore confirmed that a significant reduction of the symmetry-energy term at the freeze-out stage of reduced density and high temperature is necessary to reproduce the experimental isotope distributions. A trend of decreasing symmetry energy for large neutron-rich fragments of low excitation energy is interpreted as a nuclear-structure effect.

  20. NA49 event display of the reconstructed tracks emanating from the "little bang" created in a central collision of Lead projectile with a Lead nucleus

    CERN Multimedia

    1996-01-01

    When a 33 TeV Lead nucleous projectile hits head on a Lead target it creates for a brief instant of time a system of quarks and gluons that more than 100'000 times hotter than the sun. As this fireball expands it reconstitutes normal matter creating thousands of particles (pions, kaons, protons, ....). The NA49 Time Projection Chambers extending over 13 m can record a large majority of the produced charged particles. The result of a complex analysis is shown here in a event display of the reconstructed tracks. The blue lines represent the boundaries of the detectors in a perspective view from the far end of the experiment towards the interaction point, where all the tracks originate.